Checks for heat_user_domain explicitly

The script should check for heat_user_domain explicitly instead of matching on "heat"

Closes-Bug: #1839824
Change-Id: Iac83444487d2aa96a0f90086029f43922d1e7856
(cherry picked from commit 5e946cac49)

docker/heat/heat-api/extend_start.sh

@@ -4,13 +4,15 @@
 # of the KOLLA_BOOTSTRAP variable being set, including empty.
 if [[ "${!KOLLA_BOOTSTRAP[@]}" ]]; then
     heat-manage db_sync
-    CURRENT_HEAT_DOMAIN_NAME=$(openstack domain list | grep heat | awk '{print $4}')
 
-    if [[ "heat_user_domain" != "$CURRENT_HEAT_DOMAIN_NAME" ]]; then
+    EXISTING_DOMAINS=$(openstack domain list -f value -c Name)
+
+    if ! echo "$EXISTING_DOMAINS" | grep '^heat_user_domain$' &>/dev/null; then
         openstack domain create heat_user_domain
         openstack user create --domain heat_user_domain heat_domain_admin --password ${HEAT_DOMAIN_ADMIN_PASSWORD}
         openstack role add --domain heat_user_domain --user-domain heat_user_domain --user heat_domain_admin admin
     fi
+
     exit 0
 fi