Remove reviewstats unit test job config
Remove reviewstats unit test job config

This is being moved in-repo and doesn't need to be here anymore.
The publish-to-pypi template is left for consistency with other
projects, even though reviewstats is branchless and it could be moved
in-repo.

Change-Id: I7aa4deb38d557b3d0176b1ff793931e6dca26dbd
Depends-On: https://review.openstack.org/#/c/653133

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