[watcher] Transition Stein to End of Life

As announced on mailing list [1], this patch transitions the Stein
branch to End of Life. The last patch of the branch will be tagged with
stein-eol tag. stable/stein branch cannot be used anymore and will be
deleted if this patch merges.

This is needed as stable/stein is not actively maintained in recent
period, thus gates are mostly broken due to job failures. Besides,
by removing these branches, infra resources will be freed up, too.

Please try to identify any zuul job, that is defined outside of the
repositories in this patch (for example in openstack-zuul-jobs, etc.)
and won't be used anymore if stable/stein is deleted. Propose a job
removal patch for them.

Please +1 if the team is ready for us to proceed with this transition,
or -1 if there are still some activity on the branch and the team wants
to continue to maintain it.

[1] https://lists.openstack.org/pipermail/openstack-discuss/2023-September/034965.html

Change-Id: I03a63511fa348041f5fe9276be38b63b30c7e9b4

deliverables/stein/python-watcherclient.yaml

@@ -15,6 +15,10 @@ releases:
     projects:
       - repo: openstack/python-watcherclient
         hash: db7a5e4bc9c46041228f1dd99fab353c41282761
+  - version: stein-eol
+    projects:
+      - repo: openstack/python-watcherclient
+        hash: 47306018ba1c92910fda46ccc2580a5076942c33
 branches:
   - location: 2.2.0
     name: stable/stein

deliverables/stein/watcher-dashboard.yaml

@@ -15,7 +15,12 @@ releases:
     projects:
       - repo: openstack/watcher-dashboard
         hash: 50437a47e418beff01038d92eed2d65714e50137
+  - version: stein-eol
+    projects:
+      - repo: openstack/watcher-dashboard
+        hash: 7a296e28a5e7bb54f6989b34a138c9596b61f52d
 branches:
   - location: 1.12.0
     name: stable/stein
-release-notes: https://docs.openstack.org/releasenotes/watcher-dashboard/stein.html
+release-notes: 
+  https://docs.openstack.org/releasenotes/watcher-dashboard/stein.html

deliverables/stein/watcher.yaml

@@ -20,6 +20,10 @@ releases:
     projects:
       - repo: openstack/watcher
         hash: 922783a5f8b30dbd7e2da95f29ce8e747b812c19
+  - version: stein-eol
+    projects:
+      - repo: openstack/watcher
+        hash: e206bc474ce9349d1f8c1d80d8053fc3958770f5
 branches:
   - location: 2.0.0.0rc1
     name: stable/stein