O problema é o ponto em update-rc.d
(em /etc/sudoers.d/update-rc.d
); de man sudo
:
The #includedir directive can be used to create a sudo.d directory that the system package manager can drop sudoers rules into as part of package installation. For example, given:
#includedir /etc/sudoers.d
sudo will read each file in /etc/sudoers.d, skipping file names that end in ~ or contain a . character to avoid causing problems with package manager or editor temporary/backup files.