Fix missing parameter in webrtc_signaling "connected" handler (#995)

networking/webrtc_signaling/demo/client_ui.gd

@@ -39,8 +39,8 @@ func _mp_peer_disconnected(id: int):
 	_log("[Multiplayer] Peer %d disconnected" % id)
 
 
-func _connected(id):
-	_log("[Signaling] Server connected with ID: %d" % id)
+func _connected(id, use_mesh):
+	_log("[Signaling] Server connected with ID: %d. Mesh: %s" % [id, use_mesh])
 
 
 func _disconnected():