[user-guides] Remove unnecessary colon
[user-guides] Remove unnecessary colon

Change-Id: I566aefad66e1f72f41d4f482dd416fb088095457
Closes-Bug: 1462307

Akasurde/openstack-manuals,AlekhyaMallina-Vedams/openstack-manuals,openstack/openstack-manuals,openstack/openstack-manuals,potsmaster/openstack-manuals,kairoaraujo/openstack-manuals,saeki-masaki/openstack-manuals,kairoaraujo/openstack-manuals,openstack/openstack-manuals,Akasurde/openstack-manuals,potsmaster/openstack-manuals,openstack/openstack-manuals,AlekhyaMallina-Vedams/openstack-manuals,AlekhyaMallina-Vedams/openstack-manuals,saeki-masaki/openstack-manuals