The package build-depends on debhelper but does not ship a compat file. Packages not using an experimental or beta compatibility level may alternatively Build-Depend on the debhelper-compat virtual package, For example:
Build-Depends: debhelper-compat (= 12)
Please refer to the debhelper documentation on how to create the compat file and the differences between each compat level.
Refer to https://lists.debian.org/debian-devel-changes/2012/01/msg01335.html and the debhelper(7) manual page for details.