[Tempest Plugins] Tag stein-last

Stein branch is in Extended Maintenance now[1]. All Tempest
plugins are branchless which means master version of Tempest
and its plugins is used to test the supported stable branches.

Once stable branch is moved to EM state then, Tempest and its
plugins compatible tag needs to be released so that we can
keep testing the EM stable branches with this tag once master
Tempest and its plugins are not compatible[2].

This tag will help for testing the stable/stein with single
compatible tag of Tempest and its plugins.

Tagging 'stein-last' as well as a new version also with same hash.
Documenting this new tag name here
- https://review.opendev.org/c/openstack/project-team-guide/+/769821

More detail on compatible version policy for Tempest and its
plugins is here
- https://docs.openstack.org/tempest/latest/tempest_and_plugins_compatible_version_policy.html

[1] https://releases.openstack.org/stein/index.html
[2] https://docs.openstack.org/tempest/latest/stable_branch_support_policy.html

Change-Id: Ic7efdcf1e01d6a743aa2c652b552928a7337ec4b

deliverables/stein/manila-tempest-plugin.yaml

@@ -17,3 +17,7 @@ releases:
     projects:
       - repo: openstack/manila-tempest-plugin
         hash: 0ac95412b1b0555775b4d45f51c27af2fa84724a
+  - version: stein-last
+    projects:
+      - repo: openstack/manila-tempest-plugin
+        hash: a5c2b7d467d03afba8a90dfd99fcc647e198ba0f

deliverables/wallaby/manila-tempest-plugin.yaml

@@ -9,3 +9,8 @@ repository-settings:
     tarball-base: manila-tempest-plugin
 team: manila
 type: tempest-plugin
+releases:
+  - version: 1.3.0
+    projects:
+      - repo: openstack/manila-tempest-plugin
+        hash: a5c2b7d467d03afba8a90dfd99fcc647e198ba0f