fix: Fix issue with unregistering client streamers

Fixed an issue where client streamers were not properly unregistered from the channel manager. Added a call to cancel the client streamer before unregistering it.

StreamMaster.Streams/Channels/ChannelManager.cs

@@ -71,6 +71,7 @@ private async void StreamManager_OnStreamingStoppedEvent(object? sender, IStream
                         clientStreamerManager.GetClientStreamerConfigurationsByChannelVideoStreamId(channelStatus.ChannelVideoStreamId)
                             .ForEach(async x =>
                             {
+                                await x.CancelClient();
                                 await UnRegisterWithChannelManager(x).ConfigureAwait(false);
                             }
                             );