Unit tests mocks on sysinv conductor manager causing an infinite recursion

[Joao Soubihe]

Brief Description
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Unit tests on py27 environment related to ManagerTestCase class are failing in tox tun by Zuul. As locally this is an intermittent error, this seems to be consistent in ubuntu-xenial tests triggered by Zuul after post review on Tox.

Severity
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Minor

Steps to Reproduce
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With latest code from StarlingX master branch, try to add a unit test at ManagerTestCase class in test_manager.py test file and submit a review on Gerrit with tox py27 tests as a gate job.

Expected Behavior
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Unit tests should pass successfully without errors

Actual Behavior
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Recursion limit exceeded;
test_deferred_multiple_runtime_config test failing.

Reproducibility
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Reproducible intermittently running tox locally. When submitting review this issue is reproduced all the times that we try to add a new unit test to ManagerTestCase class.

Branch/Pull Time/Commit
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An experimental review I opened can be seen below
https://review.opendev.org/c/starlingx/config/+/795612

Last Pass
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Just remove any unit test on the class and the tests should pass.

Timestamp/Logs
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Logs attached. We can also explore Zuul execution on the link below
https://zuul.opendev.org/t/openstack/build/ff90914a490a45a195663000697dbbca

Test Activity
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Developer Testing