feat: channel type 1<<21

Author: Lulalaby

DisCatSharp/Enums/Channel/ChannelFlags.cs

@@ -125,6 +125,11 @@ public enum ChannelFlags : long
 	/// </summary>
 	IsModeratorReportChannel = 1L << 19,
 
+	/// <summary>
+	/// 	Marks this channel as containing spoilers, so that plot twists, heavy topics, or other sensitive discussions are hidden until users choose to view.
+	/// </summary>
+	IsSpoiler = 1L << 21,
+
 	/// <summary>
 	///      The flags are unknown.
 	/// </summary>