chore(deps): update docker/build-push-action action to v6

Author: renovate[bot]

.github/workflows/docker.yml

@@ -40,7 +40,7 @@ jobs:
           username: ${{ secrets.DOCKERHUB_USERNAME }}
           password: ${{ secrets.DOCKERHUB_TOKEN }}
       - name: Build and export to Docker
-        uses: docker/build-push-action@v4
+        uses: docker/build-push-action@v6
         with:
           context: .
           load: true
@@ -54,7 +54,7 @@ jobs:
           sudo rm -rf ./data
       - name: Build and push
         id: docker_build
-        uses: docker/build-push-action@v4
+        uses: docker/build-push-action@v6
         with:
           context: .
           push: ${{ startsWith(github.ref, 'refs/tags/v') }}