/etc/cobbler/pxe/grubsystem.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 | title $profile_name
root (nd)
kernel $kernel_path $kernel_options
initrd $initrd_path
|