Merge pull request #157 from dxw/renovate/docker-build-push-action-6.x

Update docker/build-push-action action to v6

Author: mec

.github/workflows/rails-integration-tests.yml

@@ -35,7 +35,7 @@ jobs:
       - name: Set up Docker Buildx
         uses: docker/setup-buildx-action@v3
       - name: Build and cache
-        uses: docker/build-push-action@v5
+        uses: docker/build-push-action@v6
         with:
           context: .
           file: ./Dockerfile