Bump docker/build-push-action from 5 to 6

Bumps [docker/build-push-action](https://github.com/docker/build-push-action) from 5 to 6.
- [Release notes](https://github.com/docker/build-push-action/releases)
- [Commits](docker/build-push-action@v5...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/docker.yml

@@ -51,7 +51,7 @@ jobs:
           password: ${{ secrets.GITHUB_TOKEN }}
       - name: Build and push
         id: docker_build_zsh_versions
-        uses: docker/build-push-action@v5
+        uses: docker/build-push-action@v6
         timeout-minutes: 60
         with:
           push: ${{ github.event.number == 0 }}
@@ -84,7 +84,7 @@ jobs:
           password: ${{ secrets.GITHUB_TOKEN }}
       - name: Build and push
         id: docker_build_latest
-        uses: docker/build-push-action@v5
+        uses: docker/build-push-action@v6
         if: github.ref == 'refs/heads/main'
         with:
           push: true