Use CDN url for CDN helpers

src/Discord.Net/API/CDN.cs

@@ -3,14 +3,14 @@
     internal static class CDN
     {
         public static string GetApplicationIconUrl(ulong appId, string iconId)
-            => iconId != null ? $"{DiscordConfig.ClientAPIUrl}app-icons/{appId}/{iconId}.jpg" : null;
+            => iconId != null ? $"{DiscordConfig.CDNUrl}app-icons/{appId}/{iconId}.jpg" : null;
         public static string GetUserAvatarUrl(ulong userId, string avatarId)
-            => avatarId != null ? $"{DiscordConfig.ClientAPIUrl}avatars/{userId}/{avatarId}.jpg" : null;
+            => avatarId != null ? $"{DiscordConfig.CDNUrl}avatars/{userId}/{avatarId}.jpg" : null;
         public static string GetGuildIconUrl(ulong guildId, string iconId)
-            => iconId != null ? $"{DiscordConfig.ClientAPIUrl}icons/{guildId}/{iconId}.jpg" : null;
+            => iconId != null ? $"{DiscordConfig.CDNUrl}icons/{guildId}/{iconId}.jpg" : null;
         public static string GetGuildSplashUrl(ulong guildId, string splashId)
-            => splashId != null ? $"{DiscordConfig.ClientAPIUrl}splashes/{guildId}/{splashId}.jpg" : null;
+            => splashId != null ? $"{DiscordConfig.CDNUrl}splashes/{guildId}/{splashId}.jpg" : null;
         public static string GetChannelIconUrl(ulong channelId, string iconId)
-            => iconId != null ? $"{DiscordConfig.ClientAPIUrl}channel-icons/{channelId}/{iconId}.jpg" : null;
+            => iconId != null ? $"{DiscordConfig.CDNUrl}channel-icons/{channelId}/{iconId}.jpg" : null;
     }
 }