This change does the following:
- Removes the centos7 job, it uses python2 even though python2 was
dropped from IPA in 2019.
(see Ifd0e0b99bb82a7d7e82d6c14309468196f5734fc)
- Allow 60-ironic-python-agent-ramdisk-install to assume python3 and
the venv module, the remaining centos7-python3 job will also test this
- Replaces the pip-and-virtualenv element with ensure-venv.
pip-and-virtualenv exists to install virtualenv for python2
environments, and it is unmaintained and mostly technical debt.
Change-Id: I9b6e03f50a4eb2484a04748e51d7348401b6ca04
(cherry picked from commit 66206d0b27)
(cherry picked from commit e51c210861)
9ed9c56e2d