stx/openstack-armada-app uses soon-to-be deprecated pip install --use-deprecated legacy-resolver

[Ghada Khalil]

Brief Description
-----------------
Opened on behalf of <email address hidden>

The pip team is planning to depreciate the '--use-deprecated legacy-resolver'
install option. While a firm date has yet to be set, We need to be ready for
the change.

Our usage seems to be confined to 'tox.ini' files. When the upstream pip change
change is delivered, we can expect.
- Build failures due to failed unit tests
- Zuul to vote -q on code reviews in some repos

This LP tracks addressing the issue with the following files:
cgcs-root/stx/openstack-armada-app/python-k8sapp-openstack/k8sapp_openstack/tox.ini

Severity
--------
Major:

Steps to Reproduce
------------------
Scan source code with ....
grep -r 'use-deprecated' $MY_REPO

Expected Behavior
------------------
Not found

Actual Behavior
----------------
Found 8 files using the offending option

Reproducibility
---------------
100%

System Configuration
--------------------
N/A

Branch/Pull Time/Commit
-----------------------
March 9, 2022

Last Pass
---------
N/A

Timestamp/Logs
--------------
N/A

Test Activity
-------------
Build

Workaround
----------
N/A

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.opendev.org/c/starlingx/openstack-armada-app/+/835482

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.opendev.org/c/starlingx/openstack-armada-app/+/835482
Committed: https://opendev.org/starlingx/openstack-armada-app/commit/d14bbb6500d000cb550b3db5e4fb329e6d81e0f2
Submitter: "Zuul (22348)"
Branch: master

commit d14bbb6500d000cb550b3db5e4fb329e6d81e0f2
Author: Thiago Brito <email address hidden>
Date: Mon Mar 28 15:05:36 2022 -0300

    Removing deprecated resolver on tox py39 job

    The pip team is planning to depreciate the '--use-deprecated
    legacy-resolver' install option. This commit removes the only occurrence
    of this legacy resolver on our tox files.

    Closes-Bug: #1966070

    Signed-off-by: Thiago Brito <email address hidden>
    Change-Id: I653851a096d06870deea4c25dffd26dd39d756ce