Add base jobs for python_venv_build ansible role
Add base jobs for python_venv_build ansible role

Following on from https://review.openstack.org/553392
we add the base jobs for the repo to ensure a minimal
set of testing is executed against it.

Change-Id: I0939781e4f329563e9e3c9e5e509564ef367f6c5

openstack-infra/project-config,openstack-infra/project-config