[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: I4d81e998d44d132e2ec9c748301a5e22a0cda533

deliverables/stein/ec2api-tempest-plugin.yaml

@@ -8,6 +8,10 @@ releases:
       - hash: 2757fdac7355e9bd355b0e472ed928d7b88b933e
         repo: openstack/ec2api-tempest-plugin
     version: 0.2.0
+  - version: stein-last
+    projects:
+      - repo: openstack/ec2api-tempest-plugin
+        hash: ac5fb7ad47fc67304ff1cb819ff606488d522fe0
 repository-settings:
   openstack/ec2api-tempest-plugin: {}
 team: ec2-api

deliverables/wallaby/ec2api-tempest-plugin.yaml

@@ -8,3 +8,8 @@ repository-settings:
   openstack/ec2api-tempest-plugin: {}
 team: ec2-api
 type: tempest-plugin
+releases:
+  - version: 1.2.0
+    projects:
+      - repo: openstack/ec2api-tempest-plugin
+        hash: ac5fb7ad47fc67304ff1cb819ff606488d522fe0