Update docker/build-push-action action to v6

Author: renovate[bot]

.github/workflows/docker.yaml

@@ -50,7 +50,7 @@ jobs:
             type=sha
 
       - name: Build and push Docker image
-        uses: docker/build-push-action@v5.3.0
+        uses: docker/build-push-action@v6.0.0
         with:
           context: .
           push: true