Add TLS Barbican jobs against stable branches

Now not having octavia-lib as a requirement in the TLS Barbican tempest
scenario, the scenario can be tested against stable branches. This patch
adds jobs to run all the way back to stable/queens.

Change-Id: I6407b17a389f9687b7d3875b19c985196e2b485b
diff --git a/zuul.d/jobs.yaml b/zuul.d/jobs.yaml
index 65903b4..b84e55e 100644
--- a/zuul.d/jobs.yaml
+++ b/zuul.d/jobs.yaml
@@ -390,6 +390,21 @@
       devstack_localrc:
         TEMPEST_PLUGINS: '"/opt/stack/octavia-tempest-plugin /opt/stack/barbican-tempest-plugin"'
 
+- job:
+    name: octavia-v2-dsvm-tls-barbican-stable-stein
+    parent: octavia-v2-dsvm-tls-barbican
+    override-checkout: stable/stein
+
+- job:
+    name: octavia-v2-dsvm-tls-barbican-stable-rocky
+    parent: octavia-v2-dsvm-tls-barbican
+    override-checkout: stable/rocky
+
+- job:
+    name: octavia-v2-dsvm-tls-barbican-stable-queens
+    parent: octavia-v2-dsvm-tls-barbican
+    override-checkout: stable/queens
+
 # Temporary transitional aliases for gates used in other repos
 # Remove once octavia has transitioned job names
 - job: