Update 'Maintained' stable branch jobs on master gate

We have stable/yoga released and stable/ussuri is in
'Extended Maintenance' state. Current 'Maintained'
stable branches are yoga, xena, wallaby, and victoria.

As per tempest stable branch testing policy[1], adding the
newly released stable/yoga job and remove the EM stable/ussuri
job.

[1] https://docs.openstack.org/tempest/latest/stable_branch_testing_policy.html

Change-Id: I9c5984e7caabf61c10b9d211a5347799701bf3e1

.zuul.yaml

@@ -6,18 +6,23 @@
       jobs:
         - murano-tempest-api:
             voting: false
+        - murano-tempest-api-yoga:
+            voting: false
         - murano-tempest-api-xena:
             voting: false
         - murano-tempest-api-wallaby:
             voting: false
         - murano-tempest-api-victoria:
             voting: false
-        - murano-tempest-api-ussuri:
-            voting: false
         - murano-tempest-cfapi
     gate:
       queue: murano
 
+- job:
+    name: murano-tempest-api-yoga
+    parent: murano-tempest-api
+    override-checkout: stable/yoga
+
 - job:
     name: murano-tempest-api-xena
     parent: murano-tempest-api
@@ -32,9 +37,3 @@
     name: murano-tempest-api-victoria
     parent: murano-tempest-api
     override-checkout: stable/victoria
-
-- job:
-    name: murano-tempest-api-ussuri
-    parent: murano-tempest-api
-    nodeset: openstack-single-node-bionic
-    override-checkout: stable/ussuri