[install] change description of glance service to "OpenStack Image"
[install] change description of glance service to "OpenStack Image"

The service descriptions for all other services are without "service".

Change-Id: Ib35d86a7a237f9097559e524ebe12d66d17c62ec

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