Fix Interaction.channel being None in threads

discord/guild.py

@@ -586,6 +586,12 @@ class Guild(Hashable):
             channels.sort(key=lambda c: (c._sorting_bucket, c.position, c.id))
         return as_list
 
+    def _resolve_channel(self, id: Optional[int], /) -> Optional[Union[GuildChannel, Thread]]:
+        if id is None:
+            return
+
+        return self._channels.get(id) or self._threads.get(id)
+
     def get_channel(self, channel_id: int, /) -> Optional[GuildChannel]:
         """Returns a channel with the given ID.