Renovate: Update docker/build-push-action action to v7

Author: renovate[bot]

.github/workflows/container-registry-ghcr.yaml

@@ -49,7 +49,7 @@ jobs:
       - name: Set up Docker Buildx
         uses: docker/setup-buildx-action@v3
       - name: Build and push Docker image
-        uses: docker/build-push-action@v6
+        uses: docker/build-push-action@v7
         with:
           context: .
           labels: ${{ steps.meta.outputs.labels }}