There are totally 3 failures
ParallelTestTest » verifyParallel[5](false, methods, 4) 0.330s
JarFileUtilsTest » generateTestJar 0.092s
DataProviderTest » parallelDataProviderSample
The JarFileUtilsTest
failure was due to a missing xml file, which I have fixed as part of this pull request.
The other two failures, I am not aware of them failing all the time. I think it must be a sporadic failure.
I would request you to please try building the code once again (I have recently pushed in changes, which now makes TestNG need JDK8 instead of JDK7).
If you have any questions pertaining to TestNG, I would request you to please post on TestNG-users google forum (for faster responses)