setup qemu

Author: paulrostorp

.github/workflows/docker-publish.yml

@@ -43,6 +43,10 @@ jobs:
         with:
           cosign-release: 'v1.4.0'
 
+      - name: Set up QEMU
+        uses: docker/setup-qemu-action@master
+        with:
+          platforms: all
 
       # Workaround: https://github.com/docker/build-push-action/issues/461
       - name: Setup Docker buildx