lower-constraints job fail on Focal

[Bernard Cafarelli]

Requirements now pass after recent patch was merged, but UT fail with versions from lower-requirements, as seen on https://review.opendev.org/#/c/738163/:
https://storage.bhs.cloud.ovh.net/v1/AUTH_dcaab5e32b234d56b626f72581e3644c/zuul_opendev_logs_1ed/738163/16/check/openstack-tox-lower-constraints/1ed7287/testr_results.html

2 main error types:
RuntimeError: generator raised StopIteration
and
  File "/usr/lib/python3.8/ssl.py", line 720, in verify_mode
    super(SSLContext, SSLContext).verify_mode.__set__(self, value)
RecursionError: maximum recursion depth exceeded

As UT pass, this is mostly a task to find and update needed versions in lower-constraints

At least for the RecursionError one the fix is apparently bumped eventlet version

[Bernard Cafarelli (bcafarel)]

Also oslo.privsep requires eventlet 0.21.0 minimum (seen when running job locally), this sounds like a good starting point

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.opendev.org/750446

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.opendev.org/750446
Committed: https://git.openstack.org/cgit/openstack/neutron/commit/?id=db4ff00175ff450006a8d29b4d26ddeed6b3ec67
Submitter: Zuul
Branch: master

commit db4ff00175ff450006a8d29b4d26ddeed6b3ec67
Author: Bernard Cafarelli <email address hidden>
Date: Tue Sep 8 17:39:27 2020 +0200

    Bump eventlet/oslo.messaging requirements

    With older versions, lower-constraints job fails on Focal as seen in DNM
    patch https://review.opendev.org/#/c/738163/

    Change-Id: I05e0f3a3ad0abc02f97a89d63af9f58d5fa00549
    Closes-Bug: #1894857