Fix code-block in federation documentation
Fix code-block in federation documentation

There wasn't a newline before a `code-block` in the federation docs, which
didn't allow the formatting of the code block to be rendered properly.

Change-Id: If658db9b6f4458125e5d0c4ad4e727944b0e4fa7

openstack/keystone,maestro-hybrid-cloud/keystone,mahak/keystone,rajalokan/keystone,himanshu-setia/keystone,jamielennox/keystone,idjaw/keystone,jonnary/keystone,rajalokan/keystone,cernops/keystone,vivekdhayaal/keystone,openstack/keystone,maestro-hybrid-cloud/keystone,rajalokan/keystone,vivekdhayaal/keystone,ilay09/keystone,openstack/keystone,dstanek/keystone,idjaw/keystone,dstanek/keystone,klmitch/keystone,jamielennox/keystone,roopali8/keystone,takeshineshiro/keystone,ilay09/keystone,mahak/keystone,dims/keystone,jonnary/keystone,ajayaa/keystone,dims/keystone,cernops/keystone,takeshineshiro/keystone,ilay09/keystone,vivekdhayaal/keystone,dstanek/keystone,himanshu-setia/keystone,roopali8/keystone,ajayaa/keystone,mahak/keystone,klmitch/keystone