METAL-3173/publish docker image when release is published or edited

.github/workflows/image-publish.yaml

@@ -0,0 +1,28 @@
+name: Publish Docker image
+
+on:
+  release:
+    types: [published, edited]
+
+jobs:
+  build_and_release:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        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
+      - name: Login to GitHub Container Registry
+        uses: docker/login-action@v1
+        with:
+          registry: ghcr.io
+          username: ${{ github.actor }}
+          password: ${{ secrets.GITHUB_TOKEN }}
+      - name: Build and push
+        id: docker_build
+        uses: docker/build-push-action@v2
+        with:
+          push: true
+          tags: ghcr.io/kloeckner-i/db-operator:${{ github.event.release.tag_name }}