Give 2 seconds timeout because proxy.Wait(1) waits 1 second

to prevent race condition

Author: sancheolz

CoreRemoting.Tests/SessionTests.cs

@@ -203,7 +203,7 @@ public virtual async Task CloseSession_method_should_close_session_gracefully_is
             MessageEncryption = false,
             ServerPort = _serverFixture.Server.Config.NetworkPort,
             Channel = ClientChannel,
-            WaitTimeForCurrentlyProcessedMessagesOnDispose = 1000
+            WaitTimeForCurrentlyProcessedMessagesOnDispose = 2000
         });
 
         var disconnected = new TaskCompletionSource<bool>();