add workflow

Author: Indosaram

.github/workflows/action.yml

@@ -14,6 +14,6 @@ jobs:
         with:
           shuttle-api-key: ${{ secrets.SHUTTLE_API_KEY }}
           project-id: proj_0123456789
-          working-directory: "axum-react-chat-app"
+          working-directory: "axum-react-chat-app/backend"
           cargo-shuttle-version: "0.48.1"
           extra-args: --allow-dirty --debug