Add Patrole gate job for stable/train

Now we have stable/train branch ready for devstack
and so does for all service projects.

This commit adds the Patrole testing for stable/train
by adding new jobs running on stable/train version of
openstack.

Depends-On: https://review.opendev.org/#/c/701404/

Change-Id: I3655cf176f12685dd87c52d8e4979d8f8e000a38
diff --git a/.zuul.yaml b/.zuul.yaml
index 2945031..040e548 100644
--- a/.zuul.yaml
+++ b/.zuul.yaml
@@ -94,6 +94,14 @@
         RBAC_TEST_ROLES: reader
 
 - job:
+    name: patrole-member-train
+    parent: patrole-member
+    override-checkout: stable/train
+    vars:
+      devstack_localrc:
+        USE_PYTHON3: True
+
+- job:
     name: patrole-member-stein
     parent: patrole-member
     override-checkout: stable/stein
@@ -192,6 +200,7 @@
         - patrole-admin
         - patrole-member
         - patrole-reader
+        - patrole-member-train
         - patrole-member-stein
         - patrole-multinode-admin
         - patrole-multinode-member
@@ -203,4 +212,5 @@
         - patrole-member
     periodic-stable:
       jobs:
+        - patrole-member-train
         - patrole-member-stein