[config-ref-rst] Fix the index in alphabetical order
[config-ref-rst] Fix the index in alphabetical order

Change-Id: I7f48b247e0a83ca7cb8f947cac8c77bb33309cc7

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