Update stable branch jobs

The stable/2023.2 branch was cut off a while ago. Also the stable/yoga
already entered the EM phase so does not require testing.

Change-Id: I959aded71235ca8577733696f25ec8b891d925e0

.zuul.yaml

@@ -1,3 +1,9 @@
+- job:
+    name: heat-functional-2023-2
+    parent: heat-functional
+    nodeset: openstack-single-node-jammy
+    override-checkout: stable/2023.2
+
 - job:
     name: heat-functional-2023-1
     parent: heat-functional
@@ -10,12 +16,6 @@
     nodeset: openstack-single-node-focal
     override-checkout: stable/zed
 
-- job:
-    name: heat-functional-yoga
-    parent: heat-functional
-    nodeset: openstack-single-node-focal
-    override-checkout: stable/yoga
-
 - project:
     queue: heat
     templates:
@@ -25,9 +25,9 @@
       jobs:
         - heat-functional
         - heat-functional-legacy
+        - heat-functional-2023-2
         - heat-functional-2023-1
         - heat-functional-zed
-        - heat-functional-yoga
     gate:
       jobs:
         - heat-functional