build(deps): bump docker/build-push-action from 5.3.0 to 6.0.0

Bumps [docker/build-push-action](https://github.com/docker/build-push-action) from 5.3.0 to 6.0.0.
- [Release notes](https://github.com/docker/build-push-action/releases)
- [Commits](docker/build-push-action@v5.3.0...v6.0.0)

---
updated-dependencies:
- dependency-name: docker/build-push-action
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <[email protected]>

.github/workflows/release.yml

@@ -49,7 +49,7 @@ jobs:
     - name: Build with Gradle
       run: ./gradlew :server:installDist --no-daemon
     - name: build docker images
-      uses: docker/build-push-action@v5.3.0
+      uses: docker/build-push-action@v6.0.0
       with:
         context: server
         push: true