Fix double speaking "disconnected" when leader #18710

Closes #18692
Summary of the issue:

When connected as the controlling computer, disconnecting causes NVDA to speak "Disconnected" twice.
Description of user facing changes:

NVDA speaks "Disconnected" once.
Description of developer facing changes:

None
Description of development approach:

Removed superfluous ui.message from _remoteClient.client.RemoteClient.onDisconnectedAsLeader.

Author: SaschaCowley

source/_remoteClient/client.py

@@ -392,8 +392,6 @@ def onDisconnectingAsLeader(self):
 	@alwaysCallAfter
 	def onDisconnectedAsLeader(self):
 		log.info("Leader session disconnected")
-		# Translators: Presented when connection to a remote computer was interupted.
-		ui.message(_("Disconnected"))
 
 	def connectAsFollower(self, connectionInfo: ConnectionInfo):
 		transport = RelayTransport.create(