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

@@ -3,6 +3,9 @@ name: Swift Matrix
 permissions:
   contents: read
 
+env:
+  LINUX_RUNNER_MAP: '{"x86_64":"ubuntu-24.04","aarch64":"ubuntu-24.04-arm"}'
+
 on:
   workflow_call:
     inputs:
@@ -304,7 +307,7 @@ jobs:
 
   linux-build:
     name: Linux (${{ matrix.swift_version }} - ${{ matrix.os_version }} - ${{ matrix.arch }})
-    runs-on: ${{ matrix.runner }}
+    runs-on: ${{ fromJson(env.LINUX_RUNNER_MAP)[matrix.arch] }}
     strategy:
       fail-fast: false
       matrix:
@@ -316,11 +319,6 @@ jobs:
           - ${{ 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:
@@ -378,7 +376,7 @@ jobs:
 
   linux-static-sdk-build:
     name: Static Linux Swift SDK Build (${{ matrix.swift_version }} - ${{ matrix.os_version }} - ${{ matrix.arch }})
-    runs-on: ${{ matrix.runner }}
+    runs-on: ${{ fromJson(env.LINUX_RUNNER_MAP)[matrix.arch] }}
     strategy:
       fail-fast: false
       matrix:
@@ -390,11 +388,6 @@ jobs:
           - ${{ 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: