Switch to openstack upstream for python-tempestconf
Switch to openstack upstream for python-tempestconf

* https://review.openstack.org/#/c/508502/ moves python-tempestconf
  project from redhat-openstack namespace to openstack namespace.
  So we need to switch the upstream to openstack.

Change-Id: I958545e666ab93a76a06dd709187b0034b30cb1a

redhat-openstack/rdoinfo,javierpena/rdoinfo