
As per victoria cycle testing runtime and community goal[1] we need to migrate upstream CI/CD to Ubuntu Focal(20.04). Fixing: - bug#1886298 Bump the lower constraints for required deps which added python3.8 support in their later version. - pep8 error - Set bionic nodeset for py36 and py37 job. [1] https://governance.openstack.org/tc/goals/selected/victoria/migrate-ci-cd-jobs-to-ubuntu-fo$ Story: #2007865 Task: #40179 Change-Id: Ibab96807a7747738282732fe0069b9bc197da0ee