/usr/share/doc/fusiondirectory-plugin-argonaut-schema/changelog.Debian.gz is in fusiondirectory-plugin-argonaut-schema 1.0.8.8-3ubuntu2.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/share/doc/fusiondirectory-plugin-argonaut-schema/../fusiondirectory-plugin-systems-schema/changelog.Debian.gz