Update docker/build-push-action action to v6

Author: renovate[bot]

.github/workflows/docker-build.yml

@@ -48,7 +48,7 @@ jobs:
             type=raw,value=latest,enable=${{ github.event_name == 'release' }}
 
       - name: Build and push Docker image
-        uses: docker/build-push-action@v5
+        uses: docker/build-push-action@v6
         with:
           context: .
           push: true