Add Extension Methods

PluralKit.Bot/Extensions.cs

@@ -1,4 +1,5 @@
 using DSharpPlus;
+using DSharpPlus.Entities;
 
 using System.Net.WebSockets;
 
@@ -19,5 +20,10 @@ namespace PluralKit.Bot
             }
             return true;
         }
+
+        public static bool HasAvatar(this DiscordUser user)
+        {
+            return user.AvatarUrl != user.DefaultAvatarUrl;
+        }
     }
 }