Switch to using docker/metadata action to make sure labels are populated

* Swapped custom dockertag from ref to semver/sha
* Support publishing images from non main repo (easier to test)

Author: halkeye

.github/workflows/release.yml

@@ -13,11 +13,6 @@ jobs:
     steps:
       - uses: actions/checkout@v5
 
-      - name: Generate Docker Tag
-        run: |
-          echo ${{ github.ref }} | cut -d '/' -f 3 > DOCKER_TAG
-          echo "DOCKER_TAG=$(cat DOCKER_TAG)" >> $GITHUB_ENV
-
       - name: Set up QEMU
         uses: docker/setup-qemu-action@v3
 
@@ -26,6 +21,7 @@ jobs:
 
       - name: Login to Docker Hub
         uses: docker/login-action@v3
+        if: ${{ github.repository == 'movetokube/postgres-operator' }}
         with:
           username: ${{ secrets.DOCKER_USER }}
           password: ${{ secrets.DOCKER_TOKEN }}
@@ -37,14 +33,24 @@ jobs:
           username: ${{ github.repository_owner }}
           password: ${{ secrets.GITHUB_TOKEN }}
 
+      - name: Docker meta
+        id: meta
+        uses: docker/metadata-action@v5
+        with:
+          images: |
+            ghcr.io/${{ github.repository }}
+            movetokube/postgres-operator,enable=${{ github.repository == 'movetokube/postgres-operator' }}
+          tags: |
+            type=ref,event=branch
+            type=ref,event=pr
+            type=semver
+            type=sha
+
       - name: Build and push
         uses: docker/build-push-action@v6
         with:
           context: .
           platforms: linux/amd64,linux/arm64
           push: true
-          tags: |
-            ghcr.io/movetokube/postgres-operator:latest
-            ghcr.io/movetokube/postgres-operator:${{ env.DOCKER_TAG }}
-            movetokube/postgres-operator:${{ env.DOCKER_TAG }}
-            movetokube/postgres-operator:latest
+          tags: ${{ steps.meta.outputs.tags }}
+          labels: ${{ steps.meta.outputs.labels }}