Revert thread block for news channel. Add check for news channel

Co-Authored-By: Nova Fox <novamaday@gmail.com>

src/Discord.Net.Rest/Entities/Channels/RestNewsChannel.cs

@@ -25,13 +25,5 @@ namespace Discord.Rest
             return entity;
         }
         public override int SlowModeInterval => throw new NotSupportedException("News channels do not support Slow Mode.");
-
-        /// <summary>
-        ///     <b>News channels do not support thread creation with bots.</b>
-        /// </summary>
-        /// <inheritdoc/>
-        /// <exception cref="NotSupportedException"></exception>
-        public override Task<RestThreadChannel> CreateThreadAsync(string name, ThreadType type = ThreadType.PublicThread, ThreadArchiveDuration autoArchiveDuration = ThreadArchiveDuration.OneDay, IMessage message = null, bool? invitable = null, int? slowmode = null, RequestOptions options = null)
-            => throw new NotSupportedException("Cannot create threads in News channels");
     }
 }

src/Discord.Net.Rest/Entities/Channels/ThreadHelper.cs

@@ -21,6 +21,9 @@ namespace Discord.Rest
             if (type == ThreadType.PrivateThread && !features.HasFeature(GuildFeature.PrivateThreads))
                 throw new ArgumentException($"The guild {channel.Guild.Name} does not have the PRIVATE_THREADS feature!", nameof(type));
 
+            if (channel is INewsChannel && type != ThreadType.NewsThread)
+                throw new ArgumentException($"{nameof(type)} must be a {ThreadType.NewsThread} in News channels");
+
             var args = new StartThreadParams
             {
                 Name = name,

src/Discord.Net.WebSocket/Entities/Channels/SocketNewsChannel.cs

@@ -36,12 +36,5 @@ namespace Discord.WebSocket
         public override int SlowModeInterval
             => throw new NotSupportedException("News channels do not support Slow Mode.");
 
-        /// <summary>
-        ///     <b>News channels do not support thread creation with bots.</b>
-        /// </summary>
-        /// <inheritdoc/>
-        /// <exception cref="NotSupportedException"></exception>
-        public override Task<SocketThreadChannel> CreateThreadAsync(string name, ThreadType type = ThreadType.PublicThread, ThreadArchiveDuration autoArchiveDuration = ThreadArchiveDuration.OneDay, IMessage message = null, bool? invitable = null, int? slowmode = null, RequestOptions options = null)
-            => throw new NotSupportedException("Cannot create threads in News channels");
     }
 }