Do not publish doctrees
Do not publish doctrees

Currently we published the cached sphinx build data (13 MB for Install
Guides) to docs.openstack.org. This is not needed at all. Invoke
build_sphinx in such a way that .doctrees is not copied over.

Change-Id: I541e0259b896afb5d92d4d23153a7d0a27a419e6

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