Update example docker compose file to use environment variables (#56)

docker-compose.Example.yml

@@ -1,8 +1,15 @@
 services:
-  server:
+  server: 
-    command: --debug --dbaddr db --dbuser pokerogue --dbpass pokerogue --dbname pokeroguedb --gameurl http://localhost:8000 --callbackurl http://localhost:8001 
     image: ghcr.io/pagefaultgames/rogueserver:master
     restart: unless-stopped
+    environment:
+      debug: true
+      dbaddr: db
+      dbuser: pokerogue
+      dbpass: pokerogue
+      dbname: pokeroguedb
+      gameurl: http://localhost:8000
+      callbackurl: http://localhost:8001
     depends_on:
       db:
         condition: service_healthy