Remove handler on message_encryption

This event is being sent by slixmpp's EME plugin, when a message
contains an EME tag. I can already test for this myself, so I'd rather
not hook this event to remove duplicated messages.

Signed-off-by: Maxime “pep” Buquet <pep@bouah.net>

examples/echo_client.py

@@ -40,7 +40,6 @@ class EchoBot(ClientXMPP):
 
         self.add_event_handler("session_start", self.start)
         self.add_event_handler("message", self.message)
-        self.add_event_handler("message_encryption", self.message)
 
     def start(self, _event) -> None:
         """