test_execute_dummy_action_plan test failed within tempest

on devstack :

vagrant@controller:/opt/stack/tempest$ ./run_tempest.sh -N --config devstack_208/etc/tempest.conf -- watcher

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Failed 1 tests - output below:
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watcher_tempest_plugin.tests.scenario.test_execute_dummy_optim.TestExecuteDummyStrategy.test_execute_dummy_action_plan
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Captured traceback:
~~~~~~~~~~~~~~~~~~~
    Traceback (most recent call last):
      File "/opt/stack/watcher/watcher_tempest_plugin/tests/scenario/test_execute_dummy_optim.py", line 43, in test_execute_dummy_action_plan
        func=functools.partial(self.has_audit_succeeded, audit['uuid']),
    AttributeError: 'TestExecuteDummyStrategy' object has no attribute 'has_audit_succeeded'