Floating test: finalization_slash_itself

[scravy]

finalization_slash_itself flaked out in https://travis-ci.com/dtr-org/unit-e/jobs/197416124

finalization_slash_itself.py failed, Duration: 7 s
stdout:
2019-05-03T09:20:23.366000Z TestFramework (INFO): Initializing test directory /tmp/test_runner_U⋮_🏃_20190503_090129/finalization_slash_itself_86
2019-05-03T09:20:23.366000Z TestFramework (INFO): Debug file at /tmp/test_runner_U⋮_🏃_20190503_090129/finalization_slash_itself_86/node0/regtest/debug.log
Starting node 0 with args: 
Starting node 1 with args: 
Starting node 2 with args: -validating=1
Starting node 3 with args: -validating=1
2019-05-03T09:20:29.373000Z TestFramework (ERROR): Assertion failed
Traceback (most recent call last):
  File "/home/travis/build/dtr-org/unit-e/build/unit-e-i686-pc-linux-gnu/test/functional/test_framework/test_framework.py", line 203, in main
    self.run_test()
  File "/home/travis/build/dtr-org/unit-e/build/unit-e-i686-pc-linux-gnu/test/functional/finalization_slash_itself.py", line 173, in run_test
    self.test_double_votes()
  File "/home/travis/build/dtr-org/unit-e/build/unit-e-i686-pc-linux-gnu/test/functional/finalization_slash_itself.py", line 145, in test_double_votes
    assert_equal(len(fork2.getrawmempool()), 1)
  File "/home/travis/build/dtr-org/unit-e/build/unit-e-i686-pc-linux-gnu/test/functional/test_framework/util.py", line 42, in assert_equal
    raise AssertionError("not(%s)" % " == ".join(str(arg) for arg in (thing1, thing2) + args))
AssertionError: not(0 == 1)
2019-05-03T09:20:29.375000Z TestFramework (INFO): Stopping nodes
2019-05-03T09:20:29.705000Z TestFramework (WARNING): Not cleaning up dir /tmp/test_runner_U⋮_🏃_20190503_090129/finalization_slash_itself_86
2019-05-03T09:20:29.705000Z TestFramework (ERROR): Test failed. Test logging available at /tmp/test_runner_U⋮_🏃_20190503_090129/finalization_slash_itself_86/test_framework.log
2019-05-03T09:20:29.705000Z TestFramework (ERROR): Hint: Call /home/travis/build/dtr-org/unit-e/build/unit-e-i686-pc-linux-gnu/test/functional/combine_logs.py '/tmp/test_runner_U⋮_🏃_20190503_090129/finalization_slash_itself_86' to consolidate all logs

log.txt