DROP: Build and push image

.github/workflows/docker.yaml

@@ -0,0 +1,29 @@
+---
+name: Docker Build Action
+on:
+  push:
+
+jobs:
+  build:
+    name: Docker Build
+    runs-on: ubuntu-latest
+
+    steps:
+    - name: Log in to the container registry
+      uses: docker/login-action@v3
+      with:
+        registry: ghcr.io
+        username: ${{ secrets.DOCKER_REGISTRY_USER }}
+        password: ${{ secrets.DOCKER_REGISTRY_TOKEN }}
+
+    - name: Checkout
+      uses: actions/checkout@v4
+      with:
+        ref: ${{ github.event.pull_request.head.sha }}
+
+    - name: Build and push image
+      uses: docker/build-push-action@v5
+      with:
+        context: .
+        push: true
+        tags: ghcr.io/metal-stack/dns-controller-manager:powerdns