doc(README): update token creation instructions

- remove outdated server token retrieval command
- simplify token creation command by removing `docker compose`

🤖

README.md

@@ -26,11 +26,8 @@
 > 
 > \<prefix\>\<cluster CA hash\>::\<credentials\>
 
-Get existing server token:
-`cat /var/lib/docker/volumes/baseline_k3s-data/_data/server/token`
-
 Create new token:
-`docker compose exec -it k3s k3s token create`
+`k3s token create`
 
 #### Register Agent/Worker