/etc/cobbler/zone.template is in maas-provision-common 2.2.2-0ubuntu4.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
| 1 2 3 4 5 6 7 8 9 10 11 12 13 | \$TTL 300
@                       IN      SOA     $cobbler_server. nobody.example.com. (
                                        $serial   ; Serial
                                        600         ; Refresh
                                        1800         ; Retry
                                        604800       ; Expire
                                        300          ; TTL
                                        )
                        IN      NS      $cobbler_server.
$host_record
 |