Comment 2 for bug 2067183

Looks like there are additional tempest tests that occur that assume the dns_domain is extracted frmo the configuration files.

In order to validation to occur, we would have to update this test to use the dns_domain of the network if present.
https://opendev.org/openstack/neutron-tempest-plugin/src/commit/1a8b36e2333d5aa58e5c4621a123e4b8e911a8a5/neutron_tempest_plugin/scenario/test_internal_dns.py#L138