Fix a typo in bifrost.rst
Fix a typo in bifrost.rst

TrivialFix

Change-Id: I8d4d206c6d0b54066da1f4fd5295c317117868db

coolsvap/kolla,stackforge/kolla,dardelean/kolla-ansible,mandre/kolla,coolsvap/kolla,mandre/kolla,nihilifer/kolla,intel-onp/kolla,coolsvap/kolla,GalenMa/kolla,GalenMa/kolla,dardelean/kolla-ansible,stackforge/kolla,openstack/kolla,rahulunair/kolla,intel-onp/kolla,nihilifer/kolla,mrangana/kolla,openstack/kolla,stackforge/kolla,dardelean/kolla-ansible,mrangana/kolla,mandre/kolla,rahulunair/kolla