Add missing arg in help post archive call

Author: ChrisLovering

bot/exts/help_channels/_cog.py

@@ -125,7 +125,7 @@ async def on_thread_update(self, before: discord.Thread, after: discord.Thread)
         if after.parent_id != self.help_forum_channel.id:
             return
         if not before.archived and after.archived:
-            await _channel.help_post_archived(after)
+            await _channel.help_post_archived(after, self.scheduler)
             if after.id in self.scheduler:
                 self.scheduler.cancel(after.id)