test_list_instance_action_with_changes_before intermittently fails with "MismatchError: ['create'] != ['create', 'stop']"

Looks like bug 1795392 is still happening:

http://logs.openstack.org/14/638214/1/check/novaclient-dsvm-functional/2d72be7/job-output.txt.gz#_2019-02-21_10_34_22_068148

2019-02-21 10:34:22.068148 | primary | 2019-02-21 10:34:22.067 | {0} novaclient.tests.functional.v2.test_instance_action.TestInstanceActionCLIV266.test_list_instance_action_with_changes_before [77.038427s] ... FAILED
2019-02-21 10:34:22.070395 | primary | 2019-02-21 10:34:22.069 |
2019-02-21 10:34:22.072195 | primary | 2019-02-21 10:34:22.071 | Captured traceback:
2019-02-21 10:34:22.073917 | primary | 2019-02-21 10:34:22.073 | ~~~~~~~~~~~~~~~~~~~
2019-02-21 10:34:22.076139 | primary | 2019-02-21 10:34:22.075 | Traceback (most recent call last):
2019-02-21 10:34:22.077915 | primary | 2019-02-21 10:34:22.077 | File "novaclient/tests/functional/v2/test_instance_action.py", line 176, in test_list_instance_action_with_changes_before
2019-02-21 10:34:22.083614 | primary | 2019-02-21 10:34:22.083 | self.assertEqual(action, ['create', 'stop'])
2019-02-21 10:34:22.085490 | primary | 2019-02-21 10:34:22.084 | File "/opt/stack/new/python-novaclient/.tox/functional/lib/python2.7/site-packages/testtools/testcase.py", line 411, in assertEqual
2019-02-21 10:34:22.087854 | primary | 2019-02-21 10:34:22.087 | self.assertThat(observed, matcher, message)
2019-02-21 10:34:22.090157 | primary | 2019-02-21 10:34:22.089 | File "/opt/stack/new/python-novaclient/.tox/functional/lib/python2.7/site-packages/testtools/testcase.py", line 498, in assertThat
2019-02-21 10:34:22.092099 | primary | 2019-02-21 10:34:22.091 | raise mismatch_error
2019-02-21 10:34:22.094390 | primary | 2019-02-21 10:34:22.093 | testtools.matchers._impl.MismatchError: ['create'] != ['create', 'stop']