Remove the Pike stable branch jobs from master gate

Patrole 0.6.0 is released now, which marks the end of support
for Pike release - https://review.opendev.org/#/c/672485/

We do not need to run the Pike stable job om master gate now.

Change-Id: Id0579ce285f24c24a57c6674f93798215848441d

.zuul.yaml

@@ -116,15 +116,6 @@
       devstack_localrc:
         TEMPEST_PLUGINS: /opt/stack/patrole
 
-- job:
-    name: patrole-member-pike
-    nodeset: openstack-single-node-xenial
-    parent: patrole-member
-    override-checkout: stable/pike
-    vars:
-      devstack_localrc:
-        TEMPEST_PLUGINS: /opt/stack/patrole
-
 - job:
     name: patrole-multinode-admin
     parent: patrole-base-multinode
@@ -220,7 +211,6 @@
         - patrole-member-stein
         - patrole-member-rocky
         - patrole-member-queens
-        - patrole-member-pike
         - patrole-multinode-admin
         - patrole-multinode-member
         - patrole-extension-admin
@@ -234,4 +224,3 @@
         - patrole-member-stein
         - patrole-member-rocky
         - patrole-member-queens
-        - patrole-member-pike