[GHA] Make unit tests, benchmarks and cxx interop easier to reuse

# Motivation

Currently the `pull_request_swift_matrix` workflow provided an easy way to run a command across many Swift versions. We do have a few common commands that we want to run across the repos. Namely, unit tests, benchmarks and cxx interop.

# Modification

This PR creates new workflows for the above common matrix commands so it's easier to reuse them from other repos.

# Result

Even easier to share these workflows.

.github/workflows/benchmarks.yml

@@ -0,0 +1,38 @@
+name: Benchmarks
+
+on:
+  workflow_call:
+    inputs:
+        linux_5_8_enabled:
+            type: boolean
+            description: "Boolean to enable the Linux 5.8 Swift version matrix job. Defaults to true."
+            default: true
+        linux_5_9_enabled:
+            type: boolean
+            description: "Boolean to enable the Linux 5.9 Swift version matrix job. Defaults to true."
+            default: true
+        linux_5_10_enabled:
+            type: boolean
+            description: "Boolean to enable the Linux 5.10 Swift version matrix job. Defaults to true."
+            default: true
+        linux_nightly_6_0_enabled:
+            type: boolean
+            description: "Boolean to enable the Linux nightly 6.0 Swift version matrix job. Defaults to true."
+            default: true
+        linux_nightly_main_enabled:
+            type: boolean
+            description: "Boolean to enable the Linux nightly main Swift version matrix job. Defaults to true."
+            default: true
+
+jobs:
+    benchmarks:
+        name: Benchmarks
+        uses: ./.github/workflows/pull_request_swift_matrix.yml
+        with:
+          name: "Benchmarks"
+          matrix_linux_command: "apt-get update -y -q && apt-get install -y -q libjemalloc-dev && swift package --package-path Benchmarks/ --disable-sandbox benchmark baseline check --check-absolute-path Benchmarks/Thresholds/${SWIFT_VERSION}/"
+          matrix_linux_5_8_enabled: ${{ inputs.linux_5_8_enabled }}
+          matrix_linux_5_9_enabled: ${{ inputs.linux_5_9_enabled }}
+          matrix_linux_5_10_enabled: ${{ inputs.linux_5_10_enabled }}
+          matrix_linux_nightly_6_0_enabled: ${{ inputs.linux_nightly_6_0_enabled }}
+          matrix_linux_nightly_main_enabled: ${{ inputs.linux_nightly_main_enabled }}

.github/workflows/cxx_interop.yml

@@ -0,0 +1,38 @@
+name: Cxx interop
+
+on:
+  workflow_call:
+    inputs:
+        linux_5_8_enabled:
+            type: boolean
+            description: "Boolean to enable the Linux 5.8 Swift version matrix job. Defaults to true."
+            default: true
+        linux_5_9_enabled:
+            type: boolean
+            description: "Boolean to enable the Linux 5.9 Swift version matrix job. Defaults to true."
+            default: true
+        linux_5_10_enabled:
+            type: boolean
+            description: "Boolean to enable the Linux 5.10 Swift version matrix job. Defaults to true."
+            default: true
+        linux_nightly_6_0_enabled:
+            type: boolean
+            description: "Boolean to enable the Linux nightly 6.0 Swift version matrix job. Defaults to true."
+            default: true
+        linux_nightly_main_enabled:
+            type: boolean
+            description: "Boolean to enable the Linux nightly main Swift version matrix job. Defaults to true."
+            default: true
+
+jobs:
+    cxx-interop:
+        name: Cxx interop
+        uses: ./.github/workflows/pull_request_swift_matrix.yml
+        with:
+          name: "Cxx interop"
+          matrix_linux_command: "apt-get update -y -q && apt-get install -y -q jq && ./scripts/check-cxx-interop-compatibility.sh"
+          matrix_linux_5_8_enabled: ${{ inputs.linux_5_8_enabled }}
+          matrix_linux_5_9_enabled: ${{ inputs.linux_5_9_enabled }}
+          matrix_linux_5_10_enabled: ${{ inputs.linux_5_10_enabled }}
+          matrix_linux_nightly_6_0_enabled: ${{ inputs.linux_nightly_6_0_enabled }}
+          matrix_linux_nightly_main_enabled: ${{ inputs.linux_nightly_main_enabled }}

.github/workflows/pull_request.yml

@@ -1,43 +1,30 @@
 name: Pull Request
 
 on:
-  pull_request:
-    types: [opened, reopened, synchronize]
+    pull_request:
+      types: [opened, reopened, synchronize]
 
 jobs:
-  call-pull-request-soundness-workflow:
-    name: Soundness
-    uses: ./.github/workflows/pull_request_soundness.yml
-    with:
-      license_header_check_project_name: "SwiftNIO"
+      soundness:
+        name: Soundness
+        uses: ./.github/workflows/pull_request_soundness.yml
+        with:
+            license_header_check_project_name: "SwiftNIO"
 
-  call-pull-request-unit-tests-workflow:
-    name: Unit tests
-    uses: ./.github/workflows/pull_request_swift_matrix.yml
-    with:
-      name: "Unit tests"
-      matrix_linux_command: "swift test -Xswiftc -warnings-as-errors --explicit-target-dependency-import-check error"
-      # Disable warnings as errors: Swift 6 emits sendability warnings that haven't been dealt with yet.
-      matrix_linux_nightly_main_command_override: "swift test --explicit-target-dependency-import-check error"
-      matrix_linux_nightly_6_0_command_override: "swift test --explicit-target-dependency-import-check error"
+    unit-tests:
+        uses: ./.github/workflows/unit_tests.yml
+        with:
+            linux_nightly_6_0_arguments_override: "--explicit-target-dependency-import-check error"
+            linux_nightly_main_arguments_override: "--explicit-target-dependency-import-check error"
 
-  call-pull-request-benchmark-workflow:
-    name: Benchmarks
-    uses: ./.github/workflows/pull_request_swift_matrix.yml
-    with:
-      name: "Benchmarks"
-      matrix_linux_command: "apt-get update -y -q && apt-get install -y -q libjemalloc-dev && swift package --package-path Benchmarks/ --disable-sandbox benchmark baseline check --check-absolute-path Benchmarks/Thresholds/${SWIFT_VERSION}/"
+    benchmarks:
+        uses: ./.github/workflows/benchmarks.yml
 
-  call-pull-request-cxx-interop-workflow:
-    name: Cxx interop
-    uses: ./.github/workflows/pull_request_swift_matrix.yml
-    with:
-      name: "Cxx interop"
-      matrix_linux_command: "apt-get update -y -q && apt-get install -y -q jq && ./scripts/check-cxx-interop-compatibility.sh"
+    cxx-interop:
+        uses: ./.github/workflows/cxx_interop.yml
 
-  call-pull-request-integration-tests-workflow:
-    name: Integration tests
-    uses: ./.github/workflows/pull_request_swift_matrix.yml
-    with:
-      name: "Integration tests"
-      matrix_linux_command: "apt-get update -y -q && apt-get install -y -q lsof dnsutils netcat-openbsd net-tools curl jq && ./scripts/integration_tests.sh"
+    integration-tests:
+        uses: ./.github/workflows/pull_request_swift_matrix.yml
+        with:
+          name: "Integration tests"
+          matrix_linux_command: "apt-get update -y -q && apt-get install -y -q lsof dnsutils netcat-openbsd net-tools curl jq && ./scripts/integration_tests.sh"

.github/workflows/unit_tests.yml

@@ -0,0 +1,63 @@
+name: Unit tests
+
+on:
+  workflow_call:
+    inputs:
+        linux_5_8_enabled:
+            type: boolean
+            description: "Boolean to enable the Linux 5.8 Swift version matrix job. Defaults to true."
+            default: true
+        linux_5_8_arguments_override:
+            type: string
+            description: "The arguments passed to swift test in the Linux 5.8 Swift version matrix job."
+            default: "-Xswiftc -warnings-as-errors --explicit-target-dependency-import-check error"
+        linux_5_9_enabled:
+            type: boolean
+            description: "Boolean to enable the Linux 5.9 Swift version matrix job. Defaults to true."
+            default: true
+        linux_5_9_arguments_override:
+            type: string
+            description: "The arguments passed to swift test in the Linux 5.9 Swift version matrix job."
+            default: "-Xswiftc -warnings-as-errors --explicit-target-dependency-import-check error"
+        linux_5_10_enabled:
+            type: boolean
+            description: "Boolean to enable the Linux 5.10 Swift version matrix job. Defaults to true."
+            default: true
+        linux_5_10_arguments_override:
+            type: string
+            description: "The arguments passed to swift test in the Linux 5.10 Swift version matrix job."
+            default: "-Xswiftc -warnings-as-errors --explicit-target-dependency-import-check error"
+        linux_nightly_6_0_enabled:
+            type: boolean
+            description: "Boolean to enable the Linux nightly 6.0 Swift version matrix job. Defaults to true."
+            default: true
+        linux_nightly_6_0_arguments_override:
+            type: string
+            description: "The arguments passed to swift test in the Linux nightly 6.0 Swift version matrix job."
+            default: "-Xswiftc -warnings-as-errors --explicit-target-dependency-import-check error"
+        linux_nightly_main_enabled:
+            type: boolean
+            description: "Boolean to enable the Linux nightly main Swift version matrix job. Defaults to true."
+            default: true
+        linux_nightly_main_arguments_override:
+            type: string
+            description: "The arguments passed to swift test in the Linux nightly main Swift version matrix job."
+            default: "-Xswiftc -warnings-as-errors --explicit-target-dependency-import-check error"
+
+jobs:
+    unit-tests:
+        name: Unit tests
+        uses: ./.github/workflows/pull_request_swift_matrix.yml
+        with:
+          name: "Unit tests"
+          matrix_linux_command: "swift test -Xswiftc -warnings-as-errors --explicit-target-dependency-import-check error"
+          matrix_linux_5_8_enabled: ${{ inputs.linux_5_8_enabled }}
+          matrix_linux_5_8_command_override: "swift test ${{ inputs.linux_5_8_arguments_override }}"
+          matrix_linux_5_9_enabled: ${{ inputs.linux_5_9_enabled }}
+          matrix_linux_5_9_command_override: "swift test ${{ inputs.linux_5_9_arguments_override }}"
+          matrix_linux_5_10_enabled: ${{ inputs.linux_5_10_enabled }}
+          matrix_linux_5_10_command_override: "swift test ${{ inputs.linux_5_10_arguments_override }}"
+          matrix_linux_nightly_6_0_enabled: ${{ inputs.linux_nightly_6_0_enabled }}
+          matrix_linux_nightly_6_0_command_override: "swift test ${{ inputs.linux_nightly_6_0_arguments_override }}"
+          matrix_linux_nightly_main_enabled: ${{ inputs.linux_nightly_main_enabled }}
+          matrix_linux_nightly_main_command_override: "swift test ${{ inputs.linux_nightly_main_arguments_override }}"