Caracal: Build heat images by default

Heat is now disabled by default, but we still need to build images for
those environments that continue to use it.

Author: markgoddard

etc/kayobe/environments/ci-builder/stackhpc-ci.yml

@@ -15,6 +15,7 @@ kolla_enable_cloudkitty: true
 kolla_enable_designate: true
 kolla_enable_etcd: true
 kolla_enable_grafana: true
+kolla_enable_heat: true
 kolla_enable_influxdb: true
 kolla_enable_ironic: true
 kolla_enable_letsencrypt: true