this package seems to have new commits in its VCS but has
not yet updated debian/changelog. You should consider updating
the Debian changelog and uploading this new version into the archive.
Here are the relevant commit logs:
Author: Hideki Yamane <email@example.com>
Date: Tue Oct 8 00:02:24 2019 +0900
drop Build-Depends: debhelper, just debhelper-compat is enough