Bump docker/build-push-action from 4 to 6

Bumps [docker/build-push-action](https://github.com/docker/build-push-action) from 4 to 6.
- [Release notes](https://github.com/docker/build-push-action/releases)
- [Commits](docker/build-push-action@v4...v6)

---
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/cinder-oss-build-and-test.yml

@@ -39,7 +39,7 @@ jobs:
           # note: `/` in the branch name (e.g "cinder/3.10") are auto-converted to `-` by this action
           tags: type=sha,prefix={{branch}}.
       - name: Build and push Cinder Docker image
-        uses: docker/build-push-action@v4
+        uses: docker/build-push-action@v6
         with:
           context: .
           tags: ${{ steps.buildmeta.outputs.tags }}
@@ -62,7 +62,7 @@ jobs:
             type=ref,event=branch
             type=raw,value=latest,enable=${{ github.ref == format('refs/heads/{0}', github.event.repository.default_branch) }}
       - name: Publish new version of latest Cinder Docker images
-        uses: docker/build-push-action@v4
+        uses: docker/build-push-action@v6
         with:
           context: .
           push: true
@@ -85,7 +85,7 @@ jobs:
             type=ref,event=branch
             type=raw,value=latest,enable=${{ github.ref == env.CINDER_EXPLORER_AUTO_DEPLOY_BRANCH }}
       - name: Build and Push Cinder Explorer Docker Images
-        uses: docker/build-push-action@v4
+        uses: docker/build-push-action@v6
         with:
           context: .
           push: true