After adding `localhost` to inventory explicitly [1] this caused an interesting
side-effect, where a record for `localhost` is being added to the managed block
in /etc/hosts file, which might override FQDN defenition for the host.
This also makes healthcheck-hosts.yml fail the test, since expected record is not present.
[1] https://review.opendev.org/c/openstack/openstack-ansible/+/899523
Change-Id: If1840530a54aa9ae22eda1d3094f0c40ab66ddde