Update .zuul.yaml to use PTI job, update tox.ini to use the common way
to run sphinx, update setup.cfg for handling warnings as errors.
Change-Id: Id21dc212f17397b98c89fff047d5a4f83fa5409f
This is a mechanically generated patch to complete step 1 of moving
the zuul job settings out of project-config and into each project
repository.
Because there will be a separate patch on each branch, the branch
specifiers for branch-specific jobs have been removed.
Because this patch is generated by a script, there may be some
cosmetic changes to the layout of the YAML file(s) as the contents are
normalized.
See the python3-first goal document for details:
https://governance.openstack.org/tc/goals/stein/python3-first.html
Change-Id: Idba7f7126dc043f9e6188424936b17027e36d890
Story: #2002586
Task: #24760
Tony Breeds