Test Failure : TransportAllUsesLongPollingWhenServerOnlySupportLongPolling() 

Failed on this build: https://dev.azure.com/dnceng/public/_build/results?buildId=116342&view=logs
```
com.microsoft.signalr.HubConnectionTest > TransportAllUsesLongPollingWhenServerOnlySupportLongPolling() FAILED
      java.lang.RuntimeException at HubConnectionTest.java:1245
          Caused by: java.lang.Exception at HubConnectionTest.java:1245
```