build(deps): Bump docker/build-push-action from 2.7.0 to 2.9.0 (#467)

Bumps [docker/build-push-action](https://github.com/docker/build-push-action) from 2.7.0 to 2.9.0.
- [Release notes](https://github.com/docker/build-push-action/releases)
- [Commits](docker/build-push-action@v2.7.0...v2.9.0)

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

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

Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
Co-authored-by: Robert Zaremba <[email protected]>

.github/workflows/docker.yml

@@ -48,7 +48,7 @@ jobs:
           password: ${{ secrets.DOCKERHUB_TOKEN }}
 
       - name: Publish to Docker Hub
-        uses: docker/build-push-action@v2.7.0
+        uses: docker/build-push-action@v2.9.0
         with:
           file: ./Dockerfile
           push: ${{ github.event_name != 'pull_request' }}