fix API name in README

Author: danthe1st

README.md

@@ -70,7 +70,7 @@ For more information on how this works, visit the [DIH4JDA Wiki!](https://github
 #### `GET` `guilds/{guild_id}/leaderboard/experience?page=1`
 - A paginated endpoint which responds with an ordered list of users, based on their help channel experience.
 
-You can try out the API yourself on `api.javadiscord.net`!
+You can try out the API yourself on `api.discordjug.net`!
 
 # Credits