Attempt publishing arm docker base image

.github/workflows/vcpkg_docker_amd64.yml

@@ -28,13 +28,13 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        # arch is to tag docker images for uniqueness
-        host:
-          - { name: 'ubuntu-22.04', arch: '' }
         container:
           - { version: '22.04', codename: 'jammy' }
+        platform:
+          - 'linux/amd64'
+          - 'linux/arm64/v8' # Apple Silicon Linux support
 
-    runs-on: ${{ matrix.host.name }}
+    runs-on: ubuntu-22.04
 
     permissions:
       packages: write
@@ -53,7 +53,7 @@ jobs:
           if [[ "${GITHUB_REF}" != "refs/heads/master" ]] ; then
             test_name="test-${BRANCH_NAME////_}-"
           fi
-          echo "IMAGE_NAME=ghcr.io/lifting-bits/cxx-common/${test_name}vcpkg-builder-ubuntu-${{ env.IMAGE_VER }}:${{ matrix.container.version }}${{ matrix.host.arch }}" >> ${GITHUB_ENV}
+          echo "IMAGE_NAME=ghcr.io/lifting-bits/cxx-common/${test_name}vcpkg-builder-ubuntu-${{ env.IMAGE_VER }}:${{ matrix.container.version }}" >> ${GITHUB_ENV}
 
       - name: Build image
         working-directory: docker
@@ -63,6 +63,7 @@ jobs:
 
           docker build -f Dockerfile.ubuntu.vcpkg \
               --no-cache \
+              --platform "${{ matrix.platform }}" \
               --target caching \
               --build-arg "DISTRO_VERSION=${{ matrix.container.codename }}" \
               -t "${IMAGE_NAME}" \

docker/build.sh

@@ -9,7 +9,7 @@ set -euo pipefail
 IMAGE_VER=v2
 
 # Ubuntu versions to build
-UBUNTU_VERSION_MATRIX=( "focal" "jammy" )
+UBUNTU_VERSION_MATRIX=( "jammy" )
 
 for version in "${UBUNTU_VERSION_MATRIX[@]}"; do
   # Always pull from upstream