Add stable/wallaby job on master gate

stable/wallaby is not supported stable branch and
we are in Xena cycle development so adding wallaby
job on master so that we keep testing branchless
Patrole for all maintained stable branches.

Change-Id: If7106cdff4dbf30b549bf9e5e4fddf1ed5156070
diff --git a/.zuul.yaml b/.zuul.yaml
index a9fd103..5b54009 100644
--- a/.zuul.yaml
+++ b/.zuul.yaml
@@ -101,6 +101,11 @@
       tempest_exclude_regex: patrole_tempest_plugin.tests.api.volume.test_volume_types_extra_specs_rbac.VolumeTypesExtraSpecsRbacTest.test_show_volume_type_extra_specs
 
 - job:
+    name: patrole-member-wallaby
+    parent: patrole-member
+    override-checkout: stable/wallaby
+
+- job:
     name: patrole-member-victoria
     parent: patrole-member
     override-checkout: stable/victoria
@@ -220,6 +225,7 @@
         - patrole-admin
         - patrole-member
         - patrole-reader
+        - patrole-member-wallaby
         - patrole-member-victoria
         - patrole-member-ussuri
         - patrole-multinode-admin
@@ -235,5 +241,6 @@
         - patrole-reader
     periodic-stable:
       jobs:
+        - patrole-member-wallaby
         - patrole-member-victoria
         - patrole-member-ussuri