Vitrage tempests now use Mistral.
Add mistral to $PROJECTS
export PROJECTS="openstack/vitrage $PROJECTS"
export PROJECTS="openstack/vitrage-dashboard $PROJECTS"
export PROJECTS="openstack/aodh $PROJECTS"
+ export PROJECTS="openstack/mistral $PROJECTS"
export ENABLED_SERVICES=tempest
if [ "{python}" == "py35" ] ; then
