[designate] Transition Yoga to Unmaintained

With the new TC resolution the community replaces Extended Maintenance
with Unmaintained status [1].

So this patch transitions stable/yoga branch to Unmaintained as follows:
- tip of the stable/yoga branch is tagged with yoga-eom tag
- unmaintained/yoga branch will be cut from yoga-eom tag
- stable/yoga branch will be deleted

Some further notes:
- there will no longer be official releases off of yoga branch
- backports can be pushed against unmaintained/yoga branch
- openstack-unmaintained-core and <project>-unmaintained-core groups
  will have the rights to merge patches

For further details please read the resolution [1] & review and +1 this
patch if this is correct as soon as possible.

[1] https://governance.openstack.org/tc/resolutions/20230724-unmaintained-branches.html

Change-Id: Ib3c4a8314bf41fd0e977b1a8b2b999479cb160d6

deliverables/yoga/designate-dashboard.yaml

@@ -20,8 +20,14 @@ releases:
     projects:
       - repo: openstack/designate-dashboard
         hash: f2e7a138aabe28d61e7a512c6b2fedd251cc2342
+  - version: yoga-eom
+    projects:
+      - repo: openstack/designate-dashboard
+        hash: f2e7a138aabe28d61e7a512c6b2fedd251cc2342
 branches:
   - name: stable/yoga
     location: 14.0.0.0rc1
+  - name: unmaintained/yoga
+    location: yoga-eom
 release-notes:
   https://docs.openstack.org/releasenotes/designate-dashboard/yoga.html

deliverables/yoga/designate.yaml

@@ -38,7 +38,13 @@ releases:
     projects:
       - repo: openstack/designate
         hash: 3cce8991b85af30960d65541a2e84532f01aa4e1
+  - version: yoga-eom
+    projects:
+      - repo: openstack/designate
+        hash: 3cce8991b85af30960d65541a2e84532f01aa4e1
 branches:
   - name: stable/yoga
     location: 14.0.0.0rc1
+  - name: unmaintained/yoga
+    location: yoga-eom
 release-notes: https://docs.openstack.org/releasenotes/designate/yoga.html

deliverables/yoga/python-designateclient.yaml

@@ -19,7 +19,14 @@ releases:
     projects:
       - repo: openstack/python-designateclient
         hash: 06887d653894dc539cc4af0652ee20ff2105f65d
+  - version: yoga-eom
+    projects:
+      - repo: openstack/python-designateclient
+        hash: 8820558b01f78102b34352c7b1c22ac365171c38
 branches:
   - name: stable/yoga
     location: 4.5.0
-release-notes: https://docs.openstack.org/releasenotes/python-designateclient/yoga.html
+  - name: unmaintained/yoga
+    location: yoga-eom
+release-notes:
+  https://docs.openstack.org/releasenotes/python-designateclient/yoga.html