Added steps to help x-platform docker builds

Author: ssddanbrown

.github/workflows/docker-publish.yml

@@ -32,6 +32,12 @@ jobs:
       - name: Checkout repository
         uses: actions/checkout@v2
 
+      - name: Set up QEMU
+        uses: docker/setup-qemu-action@v1
+
+      - name: Set up Docker Buildx
+        uses: docker/setup-buildx-action@v1
+
       # https://github.com/docker/login-action
       - name: Login to GitHub Container Registry
         if: github.event_name != 'pull_request'