Add zuul-cloner-test environment
Add zuul-cloner-test environment

This is needed for some OpenStack CI testing, it will be removed once
the job is working correctly.

Related Change: I7343d54185a896b847d6340532bdab22465e98f0
Change-Id: Ib6d45031866790ee73000cf514e1263a7e8dff69

openstack/openstack-manuals,AlekhyaMallina-Vedams/openstack-manuals,openstack/openstack-manuals,AlekhyaMallina-Vedams/openstack-manuals,openstack/openstack-manuals,AlekhyaMallina-Vedams/openstack-manuals,openstack/openstack-manuals