[OVN] Use the OVN agent in "neutron-tempest-plugin-ovn"

Now, only in master (Caracal 2024.1), the "neutron-tempest-plugin-ovn"
job used the OVN agent with the metadata extension, instead of the
OVN metadata agent. This functionality is implemented in the referred
link.

The OVN agent won't be used in stable releases.

Depends-On: https://review.opendev.org/c/openstack/neutron/+/898238

Related-Bug: #2017871
Change-Id: I92b85ec1ac609ada18fc1185e56f07c36d353518
diff --git a/zuul.d/master_jobs.yaml b/zuul.d/master_jobs.yaml
index 6b41f87..d7b6732 100644
--- a/zuul.d/master_jobs.yaml
+++ b/zuul.d/master_jobs.yaml
@@ -603,6 +603,7 @@
           (^neutron_tempest_plugin.scenario.test_mtu.NetworkWritableMtuTest)"
       devstack_localrc:
         Q_AGENT: ovn
+        OVN_AGENT_EXTENSIONS: 'metadata'
         NETWORK_API_EXTENSIONS: "{{ (network_api_extensions_common + network_api_extensions_ovn) | join(',') }}"
         Q_ML2_PLUGIN_MECHANISM_DRIVERS: ovn,logger
         Q_ML2_PLUGIN_TYPE_DRIVERS: local,flat,vlan,geneve
@@ -624,7 +625,8 @@
       devstack_services:
         br-ex-tcpdump: true
         br-int-flows: true
-        q-ovn-metadata-agent: true
+        q-ovn-metadata-agent: false
+        q-ovn-agent: true
         ovn-controller: true
         ovn-northd: true
         ovs-vswitchd: true