Change docstring for Client.send_message to point to a valid property.

discord/client.py

@@ -897,7 +897,7 @@ class Client:
         For convenience it could also be a :class:`User`. If it's a :class:`User` or :class:`PrivateChannel`
         then it sends the message via private message, otherwise it sends the message to the channel.
         If the destination is a :class:`Server` then it's equivalent to calling
-        :meth:`Server.get_default_channel` and sending it there.
+        :attr:`Server.default_channel` and sending it there.
 
         If it is a :class:`Object` instance then it is assumed to be the
         destination ID. The destination ID is a *channel* so passing in a user