Update build.yml

.github/workflows/build.yml

@@ -232,7 +232,7 @@ jobs:
                 uses: docker/build-push-action@v2
                 with:
                     context: ./dist
-                    file: ./dist/Dockerfile
+                    file: ./dist/demo.Dockerfile
                     platforms: linux/amd64
                     push: ${{ github.event_name != 'pull_request' }}
                     tags: |