[mistral] Transition Xena to EM

This transition the stable/xena 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 after the transition.

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.

The transition deadline is April 20th, 2023.

Change-Id: Ia51d71dc15fbce542c549eb9319a03e936e8dc3a

deliverables/xena/mistral-dashboard.yaml

@@ -16,6 +16,10 @@ releases:
       - repo: openstack/mistral-dashboard
         hash: 2980dfc44f11400c75a1113e468f50e7c6d6396c
     diff-start: 12.0.0
+  - version: xena-em
+    projects:
+      - repo: openstack/mistral-dashboard
+        hash: 2980dfc44f11400c75a1113e468f50e7c6d6396c
 branches:
   - name: stable/xena
     location: 13.0.0.0rc1

deliverables/xena/mistral-extra.yaml

@@ -11,6 +11,10 @@ releases:
     projects:
       - repo: openstack/mistral-extra
         hash: acd70beba1bdf7189291a6a1a65ce45393ecac6d
+  - version: xena-em
+    projects:
+      - repo: openstack/mistral-extra
+        hash: acd70beba1bdf7189291a6a1a65ce45393ecac6d
 branches:
   - name: stable/xena
     location: 11.1.0

deliverables/xena/mistral-lib.yaml

@@ -11,6 +11,10 @@ releases:
     projects:
       - repo: openstack/mistral-lib
         hash: 44c33f2ccd8b059f68db59114c71ba95dfae574d
+  - version: xena-em
+    projects:
+      - repo: openstack/mistral-lib
+        hash: 44c33f2ccd8b059f68db59114c71ba95dfae574d
 branches:
   - name: stable/xena
     location: 2.5.0

deliverables/xena/mistral.yaml

@@ -16,6 +16,10 @@ releases:
       - repo: openstack/mistral
         hash: b2d6de569c7bba96cd3179189ffbcee6b7a28c1f
     diff-start: 12.0.0
+  - version: xena-em
+    projects:
+      - repo: openstack/mistral
+        hash: b2d6de569c7bba96cd3179189ffbcee6b7a28c1f
 branches:
   - name: stable/xena
     location: 13.0.0.0rc1

deliverables/xena/python-mistralclient.yaml

@@ -11,6 +11,10 @@ releases:
     projects:
       - repo: openstack/python-mistralclient
         hash: 608ec45cef72d822d1242e0aefcea7d044662adc
+  - version: xena-em
+    projects:
+      - repo: openstack/python-mistralclient
+        hash: 608ec45cef72d822d1242e0aefcea7d044662adc
 branches:
   - name: stable/xena
     location: 4.3.0