Stable branches till stable/rocky is using python
version <py3.6. Tempest test those branch in venv
but Tempest tox use the master upper-constraint
which block installation due to dependencies
require >=py3.6. For exmaple, oslo.concurrency 4.0.0
is not compatible for <py3.6.
As we pin Tempest for EM stable brach, we should be
able to use stable constraint for Tempest installation
as well as while running during run-tempest playbook.
tox.ini is hard coded to use master constraint which force
run-tempest to recreate the tox env and use the master constraint.
Fix for that- https://review.opendev.org/#/c/705870/
Update pre-upgrade tests set to alias with ocata grenade tests
Also update Fedora image ref for test jobs.
Fedora-Cloud-Base-29-1.2.x86_64 is removed from openstack local mirro.
Update to use Fedora-Cloud-Base-30-1.2.x86_64 for test jobs.