void HandleTestAssemblyFinished(MessageHandlerArgs <ITestAssemblyFinished> args)
        {
            lock (clientLock)
            {
                assembliesInFlight--;

                if (assembliesInFlight == 0)
                {
                    // Drain the queue
                    client.WaitOne(CancellationToken.None);
                    client.Dispose();
                    client = null;
                }
            }
        }