[kolla] Transition Stein to EM

This transition the stein branch to extended maintenance.
Changes for bugfixes and things the team deems important are
still encouraged, but there will no longer be official releases
off of the branch.

Please +1 if the team is ready for us to proceed with this
transition, or -1 if there are any final backports currently in
flight that we should wait for. For the latter case, please
update the patch with the new commit hash after doing a final
release to get those changes out so we know to proceed with the
transition.

Change-Id: Ifbe2f7a4fac0d7c5b193737a19479a924166f9b3

deliverables/stein/kolla-ansible.yaml

@@ -46,4 +46,8 @@ releases:
     projects:
       - repo: openstack/kolla-ansible
         hash: 7467b7db959b160a2a404f61a318a2d9740dc2e7
+  - version: stein-em
+    projects:
+      - repo: openstack/kolla-ansible
+        hash: 7467b7db959b160a2a404f61a318a2d9740dc2e7
 release-notes: https://docs.openstack.org/releasenotes/kolla-ansible/stein.html

deliverables/stein/kolla.yaml

@@ -46,6 +46,10 @@ releases:
     projects:
       - repo: openstack/kolla
         hash: 7bd72afbb4ad269f78a04279d8f59b5701c6f871
+  - version: stein-em
+    projects:
+      - repo: openstack/kolla
+        hash: 7bd72afbb4ad269f78a04279d8f59b5701c6f871
 cycle-highlights:
   - Completed addition of images and playbooks for the OpenStack Monitoring
     service, Monasca.