Update v5.0.0.md

Author: keroxp

changelogs/v5.0.0.md

@@ -26,7 +26,7 @@ It's simple, but ECS users haven't had an equivalent feature.
 $ cage audit --region us-east-1 --cluster default --service my-service
 ```
 
-where `./.deploy/service` is a directory containing `service.json` with `cluster` and `service` fields defined.
+where `./.deploy/service` is a directory containing `service.json` with `cluster` and `serviceName` fields defined.
 
 ```bash
 $ cage audit --region us-east-1 ./.deploy/service