Migrated from keys to set datastructure in Redis

config.json.sample

@@ -3,6 +3,7 @@
     "owner_ids": [194545408960102400, 190875175460405249],
     "prefixes": ["ck!"],
     "redis_url": "",
+    "redis_prefix": "",
     "lavalink": {
         "host": "",
         "port": 2333,
@@ -19,5 +20,5 @@
     },
     "cogs": ["cogs.owner", "cogs.settings", "cogs.information", "cogs.music"],
     "slash_command_guilds": [],
-    "queue_buffer_size": 5
+    "queue_buffer_size": 5,
 }