Undid test value

src/Discord.Net/API/Client/GatewaySocket/OpCodes.cs

@@ -19,6 +19,6 @@
         /// <summary> C←S - Used to notify a client that they must reconnect to another gateway. </summary>
         Redirect = 7,
         /// <summary> C→S - Used to request all members that were withheld by large_threshold </summary>
-        RequestGuildMembers = 99
+        RequestGuildMembers = 8
     }
 }