baby steps towards multi-platform images

Author: joemaller

.github/workflows/push-to-dockerhub.yml

@@ -21,7 +21,17 @@ jobs:
     runs-on: ubuntu-20.04
 
     steps:
-      - uses: actions/checkout@v2
+      - uses: actions/checkout@v3
+
+      - name: Set up QEMU
+        uses: docker/setup-qemu-action@v2
+
+      - name: Set up Docker Buildx
+        id: buildx
+        uses: docker/setup-buildx-action@v2
+
+      - name: Available platforms
+        run: echo ${{ steps.buildx.outputs.platforms }}
 
       - name: Set up REPO and TAG environment vars
         run: |