Update Docker compose command

Author: bowenwr

examples/chem-sync-local-flask/README.md

@@ -27,10 +27,11 @@ touch .client_secret
 Start Docker:
 
 ```bash
-docker compose build
-docker compose up
+docker compose up --build -d
 ```
 
+Tip: You can omit the `-d` option if you want to run in the foreground. Otherwise, use `docker compose logs -f` to tail logs.
+
 You can verify that Flask is up and running:
 
 ```bash