Run the tests on stable/victoria as well, remove stein

So that changes to this plugin (at least, most of them) don't break
victoria.

As stein moved to EM, remove its job according the common guidelines.

Change-Id: If4857a8beaa46b48c0f7d44ff707dd44425b530c
diff --git a/.zuul.yaml b/.zuul.yaml
index 6f0ce48..58e1095 100644
--- a/.zuul.yaml
+++ b/.zuul.yaml
@@ -9,9 +9,9 @@
             voting: false
         - cinder-tempest-plugin-lvm-tgt-barbican
         - cinder-tempest-plugin-cbak-ceph
+        - cinder-tempest-plugin-basic-victoria
         - cinder-tempest-plugin-basic-ussuri
         - cinder-tempest-plugin-basic-train
-        - cinder-tempest-plugin-basic-stein
     gate:
       jobs:
         - cinder-tempest-plugin-lvm-lio-barbican
@@ -137,6 +137,12 @@
       - ^releasenotes/.*$
 
 - job:
+    name: cinder-tempest-plugin-basic-victoria
+    parent: cinder-tempest-plugin-basic
+    nodeset: openstack-single-node-focal
+    override-checkout: stable/victoria
+
+- job:
     name: cinder-tempest-plugin-basic-ussuri
     parent: cinder-tempest-plugin-basic
     nodeset: openstack-single-node-bionic
@@ -150,12 +156,3 @@
     vars:
       devstack_localrc:
         USE_PYTHON3: True
-
-- job:
-    name: cinder-tempest-plugin-basic-stein
-    parent: cinder-tempest-plugin-basic
-    nodeset: openstack-single-node-bionic
-    override-checkout: stable/stein
-    vars:
-      devstack_localrc:
-        USE_PYTHON3: True