File in /etc/sudoers.d file not being read by sudo
From the sudoers man page:
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.dsudo 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.