Bump the github-actions group with 2 updates

Bumps the github-actions group with 2 updates: [docker/setup-buildx-action](https://github.com/docker/setup-buildx-action) and [docker/build-push-action](https://github.com/docker/build-push-action).


Updates `docker/setup-buildx-action` from 3 to 4
- [Release notes](https://github.com/docker/setup-buildx-action/releases)
- [Commits](docker/setup-buildx-action@v3...v4)

Updates `docker/build-push-action` from 6 to 7
- [Release notes](https://github.com/docker/build-push-action/releases)
- [Commits](docker/build-push-action@v6...v7)

---
updated-dependencies:
- dependency-name: docker/setup-buildx-action
  dependency-version: '4'
  dependency-type: direct:production
  update-type: version-update:semver-major
  dependency-group: github-actions
- dependency-name: docker/build-push-action
  dependency-version: '7'
  dependency-type: direct:production
  update-type: version-update:semver-major
  dependency-group: github-actions
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

.github/workflows/ci.yml

@@ -73,9 +73,9 @@ jobs:
       - name: Checkout cedar-examples
         uses: actions/checkout@v6
       - name: Set up Docker Buildx
-        uses: docker/setup-buildx-action@v3
+        uses: docker/setup-buildx-action@v4
       - name: Build Docker image
-        uses: docker/build-push-action@v6
+        uses: docker/build-push-action@v7
         with:
           push: false
           context: oopsla2024-benchmarks