Stop enabling g-reg by default

Per [1] Glance registry should not be required to run since Queens.

[1] https://specs.openstack.org/openstack/glance-specs/specs/queens/approved/glance/deprecate-registry.html

Change-Id: I93325cbd26dbc6a30062d9ba83acab248897b18e
Depends-on: https://review.opendev.org/702707
Related-bug: #1859847
diff --git a/stackrc b/stackrc
index 2d3a599..9fd7f75 100644
--- a/stackrc
+++ b/stackrc
@@ -69,7 +69,7 @@
     # Placement service needed for Nova
     ENABLED_SERVICES+=,placement-api,placement-client
     # Glance services needed for Nova
-    ENABLED_SERVICES+=,g-api,g-reg
+    ENABLED_SERVICES+=,g-api
     # Cinder
     ENABLED_SERVICES+=,c-sch,c-api,c-vol
     # Neutron