remove pypy jobs from remaining oslo libraries
oslotest and stevedore were left out when we dropped the pypy jobs in
the past, so clean them up now.
- system-required
- openstack-python-jobs
- openstack-python35-jobs
- - openstack-pypy-jobs-nonvoting
- publish-openstack-sphinx-docs-python3
- check-requirements
- release-notes-jobs-python3
- system-required
- openstack-python-jobs
- openstack-python35-jobs
- - openstack-pypy-jobs-nonvoting
- check-requirements
- lib-forward-testing
- publish-openstack-sphinx-docs-python3
