nova-api-proxy fails pep8 in zuul

[Al Bailey]

Brief Description
-----------------
Zuul is failing when submitting against nfv, due to a pep8 error in nova-api-proxy

Severity
--------
Major - Blocks merges to nfv

Steps to Reproduce
------------------
Submit a code review to nfv repo and wait for zuul to fail

Expected Behavior
------------------
Submit a code review to nfv repo and wait for zuul to pass, unless the issue is the new code.

Actual Behavior
----------------
Submit a code review to nfv repo and wait for zuul to fail

Reproducibility
---------------
Started recently

System Configuration
--------------------
Dev submissions

Branch/Pull Time/Commit
-----------------------
Dec 1, 2020 (maybe earlier)

Last Pass
---------
Unknown. There are not many submissions to this repo

Timestamp/Logs
--------------
Traceback (most recent call last):
  File "/home/zuul/src/opendev.org/starlingx/nfv/nova-api-proxy/.tox/pep8/bin/flake8", line 8, in <module>
    sys.exit(main())
  File "/home/zuul/src/opendev.org/starlingx/nfv/nova-api-proxy/.tox/pep8/lib/python3.6/site-packages/flake8/main/cli.py", line 16, in main
    app.run(argv)
  File "/home/zuul/src/opendev.org/starlingx/nfv/nova-api-proxy/.tox/pep8/lib/python3.6/site-packages/flake8/main/application.py", line 396, in run
    self._run(argv)
  File "/home/zuul/src/opendev.org/starlingx/nfv/nova-api-proxy/.tox/pep8/lib/python3.6/site-packages/flake8/main/application.py", line 384, in _run
    self.run_checks()
  File "/home/zuul/src/opendev.org/starlingx/nfv/nova-api-proxy/.tox/pep8/lib/python3.6/site-packages/flake8/main/application.py", line 310, in run_checks
    self.file_checker_manager.run()
  File "/home/zuul/src/opendev.org/starlingx/nfv/nova-api-proxy/.tox/pep8/lib/python3.6/site-packages/flake8/checker.py", line 319, in run
    self.run_parallel()
  File "/home/zuul/src/opendev.org/starlingx/nfv/nova-api-proxy/.tox/pep8/lib/python3.6/site-packages/flake8/checker.py", line 288, in run_parallel
    for ret in pool_map:
  File "/usr/lib/python3.6/multiprocessing/pool.py", line 735, in next
    raise value
ValueError: not enough values to unpack (expected 2, got 0)
ERROR: InvocationError for command /home/zuul/src/opendev.org/starlingx/nfv/nova-api-proxy/.tox/pep8/bin/flake8 (exited with code 1)

Test Activity
-------------
Submissions

Workaround
----------
None, but I know how to fix this

[Al Bailey (albailey1974)]

https://review.opendev.org/c/starlingx/nfv/+/765159

[Ghada Khalil (gkhalil)]

stx.5.0 / high - issue prevents submissions to this repo

[Ghada Khalil (gkhalil)]

https://review.opendev.org/c/starlingx/nfv/+/765159
Merged 2020-12-02