Fix the expansion of the Linux host arch matrix

Author: jakepetroules

.github/workflows/pull_request.yml

@@ -26,7 +26,7 @@ jobs:
     with:
       # Linux
       linux_os_versions: '["jammy", "rhel-ubi9", "amazonlinux2"]'
-      linux_host_archs: '["x86_64", "aarch64"]'
+      linux_host_archs: '["x86_64"]'
       linux_build_command: |
         cd tests/TestPackage
         swift build

.github/workflows/swift_package_test.yml

@@ -303,24 +303,27 @@ jobs:
         timeout-minutes: 60
 
   linux-build:
-    name: Linux (${{ matrix.swift_version }} - ${{ matrix.os_version }} - ${{ matrix.arch }})
+    name: Linux (${{ matrix.swift_version }} - ${{ matrix.os_version }} - ${{ matrix.runner }})
     runs-on: ${{ matrix.runner }}
     strategy:
       fail-fast: false
       matrix:
         swift_version: ${{ fromJson(inputs.linux_swift_versions) }}
         os_version: ${{ fromJson(inputs.linux_os_versions) }}
-        arch: ${{ fromJson(inputs.linux_host_archs) }}
+        runner: ${{ 
+            fromJson(
+              contains(fromJson(inputs.linux_host_archs), 'x86_64') && !contains(fromJson(inputs.linux_host_archs), 'aarch64')
+                && '["ubuntu-24.04"]'
+                || contains(fromJson(inputs.linux_host_archs), 'aarch64') && !contains(fromJson(inputs.linux_host_archs), 'x86_64')
+                && '["ubuntu-24.04-arm"]'
+                || '["ubuntu-24.04","ubuntu-24.04-arm"]'
+            )
+          }}
         exclude:
           - ${{ fromJson(inputs.linux_exclude_swift_versions) }}
           - ${{ fromJson((!inputs.enable_linux_checks && inputs.linux_swift_versions) || '[]') }}
           - ${{ fromJson((!inputs.enable_linux_checks && inputs.linux_os_versions) || '[]') }}
           - ${{ fromJson((!inputs.enable_linux_checks && inputs.linux_host_archs) || '[]') }}
-        include:
-          - arch: x86_64
-            runner: ubuntu-24.04
-          - arch: aarch64
-            runner: ubuntu-24.04-arm
     container:
       image: ${{ (contains(matrix.swift_version, 'nightly') && 'swiftlang/swift') || 'swift' }}:${{ matrix.swift_version }}-${{ matrix.os_version }}
     steps:
@@ -377,24 +380,27 @@ jobs:
         run: ${{ inputs.linux_build_command }} ${{ (contains(matrix.swift_version, 'nightly') && inputs.swift_nightly_flags) || inputs.swift_flags }}
 
   linux-static-sdk-build:
-    name: Static Linux Swift SDK Build (${{ matrix.swift_version }} - ${{ matrix.os_version }} - ${{ matrix.arch }})
+    name: Static Linux Swift SDK Build (${{ matrix.swift_version }} - ${{ matrix.os_version }} - ${{ matrix.runner }})
     runs-on: ${{ matrix.runner }}
     strategy:
       fail-fast: false
       matrix:
         swift_version: ${{ fromJson(inputs.linux_static_sdk_versions) }}
         os_version: ${{ fromJson(inputs.linux_os_versions) }}
-        arch: ${{ fromJson(inputs.linux_host_archs) }}
+        runner: ${{ 
+            fromJson(
+              contains(fromJson(inputs.linux_host_archs), 'x86_64') && !contains(fromJson(inputs.linux_host_archs), 'aarch64')
+                && '["ubuntu-24.04"]'
+                || contains(fromJson(inputs.linux_host_archs), 'aarch64') && !contains(fromJson(inputs.linux_host_archs), 'x86_64')
+                && '["ubuntu-24.04-arm"]'
+                || '["ubuntu-24.04","ubuntu-24.04-arm"]'
+            )
+          }}
         exclude:
           - ${{ fromJson(inputs.linux_static_sdk_exclude_swift_versions) }}
           - ${{ fromJson((!inputs.enable_linux_static_sdk_build && inputs.linux_static_sdk_versions) || '[]') }}
           - ${{ fromJson((!inputs.enable_linux_static_sdk_build && inputs.linux_os_versions) || '[]') }}
           - ${{ fromJson((!inputs.enable_linux_static_sdk_build && inputs.linux_host_archs) || '[]') }}
-        include:
-          - arch: x86_64
-            runner: ubuntu-24.04
-          - arch: aarch64
-            runner: ubuntu-24.04-arm
     container:
       image: ${{ (contains(matrix.swift_version, 'nightly') && 'swiftlang/swift') || 'swift' }}:${{ matrix.swift_version }}-${{ matrix.os_version }}
     steps: