Update GitHub Action Workflow for Multi-Architecture Builds (#26)

* Fix buildx multiarch

* Update ghcr login

* second fix to ghcr login

* Update workflow for better env utilization

* Add commit hash tagging for pinned container build versions

* fix typo for github workflow env

* Use env.IMAGE_NAME for container tagging for easy changes in future

* Return pinned version for docker/login-action to v1

* Per change request, updating registry login to utilize username from secret, instead of github running actor

.github/workflows/docker.yml

@@ -8,6 +8,10 @@ on:
     paths-ignore:
       - '**.md'
 
+env:
+  REGISTRY: ghcr.io
+  IMAGE_NAME: ${{ github.repository }}
+
 jobs:
   build:
     runs-on: ubuntu-latest
@@ -27,17 +31,20 @@ jobs:
       - name: set up qemu
         uses: docker/setup-qemu-action@v1
       - name: set up buildx
+        id: docker_buildx
         uses: docker/setup-buildx-action@v1
       - name: log in to ghcr
         uses: docker/login-action@v1
         with:
-          registry: ghcr.io
-          username: lus
-          password: ${{ secrets.CR_TOKEN }}
+          registry: ${{ env.REGISTRY }}
+          username: ${{ secrets.SERVICE_USER }} # Defined in secrets for auth to registry
+          password: ${{ secrets.GITHUB_TOKEN }}
       - name: build and push
         uses: docker/build-push-action@v2
         with:
+          builder: ${{ steps.docker_buildx.outputs.name }}
+          platforms: linux/amd64, linux/arm64
           push: true
-          tags: ghcr.io/lus/pasty:${{ env.TAG }}
+          tags: ${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}:${{ env.TAG }}, ${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}:${{ env.COMMIT_HASH }}
           build-args:
-            PASTY_VERSION=${{ env.BRANCH }}-${{ env.COMMIT_HASH }}
+            PASTY_VERSION=${{ env.BRANCH }}-${{ env.COMMIT_HASH }}