Update self-hosting/installation/powersync-service-setup.mdx

Author: benitav

self-hosting/installation/powersync-service-setup.mdx

@@ -81,7 +81,7 @@ GRANT ALL PRIVILEGES ON ALL TABLES IN SCHEMA powersync TO powersync_storage_user
 ```
 
 <Tip>
-**Demo app:** A demo app with Postgres bucket storage is available [here](TODO).
+**Demo app:** A demo app with Postgres bucket storage is available [here](https://github.com/powersync-ja/self-host-demo/tree/main/demos/nodejs-postgres-bucket-storage).
 </Tip>
 
 ## PowerSync Configuration