build(deps): bump docker/build-push-action from 6.14.0 to 6.15.0 (#673)

Bumps [docker/build-push-action](https://github.com/docker/build-push-action) from 6.14.0 to 6.15.0.
- [Release notes](https://github.com/docker/build-push-action/releases)
- [Commits](docker/build-push-action@v6.14.0...v6.15.0)

---
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>

Author: dependabot[bot]

.github/workflows/buildx.yml

@@ -76,7 +76,7 @@ jobs:
           install: true
 
       - name: Docker Buildx (build)
-        uses: docker/build-push-action@v6.14.0
+        uses: docker/build-push-action@v6.15.0
         if: success() && !contains(github.ref, 'master')
         with:
           push: false
@@ -94,7 +94,7 @@ jobs:
           password: ${{ secrets.DOCKER_PASSWORD }}
 
       - name: Docker Buildx (push)
-        uses: docker/build-push-action@v6.14.0
+        uses: docker/build-push-action@v6.15.0
         if: success() && github.event_name != 'pull_request' && contains(github.ref, 'master')
         with:
           push: true