Point users towards compose in README

Author: lsileoni

README.md

@@ -47,8 +47,7 @@ This will launch Puter at http://localhost:4000 (or the next available port).
 ```bash
 git clone https://github.com/HeyPuter/puter
 cd puter
-docker build -t puter .
-docker run puter
+docker compose up
 ```
 
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