Random test fail

CI test failed with python3 once with the following message:

FAIL: test_nominal (xsocs.process.test.test_merger.TestMerger)
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Traceback (most recent call last):
  File "/home/gitlab-runner/builds/cd7cb503/0/tvincent/xsocs/py3env/lib/python3.4/site-packages/xsocs/process/test/test_merger.py", line 133, in test_nominal
    self.assertEqual(merger.status, merger.DONE, msg=merger.statusMsg)
AssertionError: 3 != 2