bug#41394: java-testng: again nondeterministic test-failures?

[Konrad Hinsen]

During today's regular "guix pull", I ran into this problem: java-testng
failed to build twice (the failures comes from the test suite), but
built correctly the third time. That's for commit:
39fa1ef033fda82cb1d122e0d1675b51acb1db34

Cheers,
  Konrad.