Add basic multi-arch build support (alexjustesen#67)

Co-authored-by: adamus1red <[email protected]>

Author: adamus1red

.github/workflows/publish-image.yml

@@ -18,6 +18,7 @@ on:
 env:
   REGISTRY: ghcr.io
   IMAGE_NAME: ${{ github.repository }}
+  PLATFORMS: linux/amd64,linux/arm64
 
 jobs:
   build-and-push-image:
@@ -30,6 +31,12 @@ jobs:
       - name: Checkout repository
         uses: actions/checkout@v3
 
+      - name: Set up QEMU
+        uses: docker/setup-qemu-action@v2
+
+      - name: Set up Docker Buildx
+        uses: docker/setup-buildx-action@v2
+
       - name: Log in to the Container registry
         uses: docker/login-action@v2
         with:
@@ -48,5 +55,6 @@ jobs:
         with:
           context: .
           push: true
+          platforms: ${{ env.PLATFORMS }}
           tags: ${{ steps.meta.outputs.tags }}
           labels: ${{ steps.meta.outputs.labels }}