Enable 'dump-interfaces' service in all devstack jobs

This simple "service" is  used by the neutron devstack plugin and runs
simple script which dumps all network interfaces from the host every 30
seconds. This can be useful for debugging purpose.

Depens-On: https://review.opendev.org/c/openstack/neutron/+/917019

Related-Bug: #2052787
Change-Id: I3680df14d09fc63c8f37caec85129f37f74b8be0

.zuul.yaml

@@ -478,6 +478,8 @@
     timeout: 7200
     vars:
       configure_swap_size: 4096
+      devstack_plugins:
+        neutron: https://opendev.org/openstack/neutron.git
       devstack_localrc:
         # Common OpenStack services settings
         SWIFT_REPLICAS: 1
@@ -502,6 +504,8 @@
         mysql: true
         rabbit: true
         tls-proxy: true
+        # Debugging/loggins servives
+        dump-interfaces: true
         # Keystone services
         key: true
         # Glance services