Use cleanCurrentPeerConnections in leaveCall.

Signed-off-by: Ivan Sein <ivan@nextcloud.com>

NextcloudTalk/NCCallController.m

@@ -200,9 +200,7 @@ static NSString * const kNCVideoTrackKind = @"video";
     [[NSNotificationCenter defaultCenter] removeObserver:self];
     _externalSignalingController.delegate = nil;
     
-    for (NCPeerConnection *peerConnectionWrapper in [_connectionsDict allValues]) {
+    [self cleanCurrentPeerConnections];
-        [peerConnectionWrapper close];
-    }
     
     [_localStream removeAudioTrack:_localAudioTrack];
     [_localStream removeVideoTrack:_localVideoTrack];