Add "neutron" devstack plugin to all tempest jobs

This plugin can enable specific neutron plugins, like e.g. QoS so
it should be enabled in all jobs which inherits from the
tempest-integrated-networking job.

Change-Id: I2655130df1210f7f175b79aec2bade28c0e1e977

zuul.d/tempest-multinode.yaml

@@ -28,6 +28,8 @@
       devstack_services:
         br-ex-tcpdump: true
         br-int-flows: true
+      devstack_plugins:
+        neutron: https://opendev.org/openstack/neutron.git
       devstack_local_conf:
         post-config:
           $NEUTRON_CONF:
@@ -58,6 +60,8 @@
               availability_zone: nova
     group-vars:
       subnode:
+        devstack_plugins:
+          neutron: https://opendev.org/openstack/neutron.git
         devstack_services:
           q-agt: true
           q-l3: true
@@ -94,6 +98,8 @@
     irrelevant-files: *irrelevant-files
     vars:
       tox_envlist: integrated-network
+      devstack_plugins:
+        neutron: https://opendev.org/openstack/neutron.git
 
 - job:
     name: neutron-ovn-multinode-base

zuul.d/tempest-singlenode.yaml

@@ -13,6 +13,8 @@
       devstack_localrc:
         Q_ML2_TENANT_NETWORK_TYPE: vxlan
         Q_ML2_PLUGIN_MECHANISM_DRIVERS: openvswitch,linuxbridge
+      devstack_plugins:
+        neutron: https://opendev.org/openstack/neutron.git
       devstack_services:
         # OVN services
         ovn-controller: false
@@ -127,6 +129,8 @@
       - openstack/neutron
       - openstack/tempest
     vars:
+      devstack_plugins:
+        neutron: https://opendev.org/openstack/neutron.git
       devstack_services:
         postgresql: true
         mysql: false
@@ -145,6 +149,8 @@
     vars:
       devstack_localrc:
         MYSQL_SERVICE_NAME: mariadb
+      devstack_plugins:
+        neutron: https://opendev.org/openstack/neutron.git
       devstack_services:
         br-ex-tcpdump: true
         br-int-flows: true
@@ -162,6 +168,9 @@
       - openstack/neutron
       - openstack/tempest
       - openstack/os-ken
+    vars:
+      devstack_plugins:
+        neutron: https://opendev.org/openstack/neutron.git
 
 - job:
     name: neutron-tempest-with-neutron-lib-master
@@ -172,6 +181,9 @@
       - openstack/neutron
       - openstack/tempest
       - openstack/neutron-lib
+    vars:
+      devstack_plugins:
+        neutron: https://opendev.org/openstack/neutron.git
 
 - job:
     name: neutron-tempest-with-uwsgi
@@ -181,6 +193,8 @@
     vars:
       devstack_localrc:
         NEUTRON_DEPLOY_MOD_WSGI: true
+      devstack_plugins:
+        neutron: https://opendev.org/openstack/neutron.git
       devstack_services:
         br-ex-tcpdump: true
         br-int-flows: true