Fix the expansion of the Linux host arch matrix

Author: jakepetroules

.github/workflows/swift_package_test.yml

@@ -304,7 +304,8 @@ jobs:
 
   linux-build:
     name: Linux (${{ matrix.swift_version }} - ${{ matrix.os_version }} - ${{ matrix.arch }})
-    runs-on: ${{ matrix.runner }}
+    runs-on: >
+      ${{ fromJson('{ "x86_64": "ubuntu-24.04", "aarch64": "ubuntu-24.04-arm" }')[matrix.arch] }}
     strategy:
       fail-fast: false
       matrix:
@@ -316,11 +317,6 @@ 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 +374,8 @@ 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('{ "x86_64": "ubuntu-24.04", "aarch64": "ubuntu-24.04-arm" }')[matrix.arch] }}
     strategy:
       fail-fast: false
       matrix:
@@ -390,11 +387,6 @@ 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: