Specify GitHub image in docker-compose directly (#204)

It's recommend to specify the full "URL" and this aligns with the Readme and default docker would search on Docker Hub, where this is not available: https://hub.docker.com/search?q=fredy%2Ffredy

docker-compose.yml

@@ -5,7 +5,7 @@ services:
     build:
       context: .
       dockerfile: Dockerfile
-    image: fredy/fredy
+    image: ghcr.io/orangecoding/fredy
     # map existing config and database
     volumes:
       - ./conf:/conf