/usr/share/doc/ruby-bson-ext/changelog.Debian.gz is in ruby-bson-ext 4.3.0-1.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/share/doc/ruby-bson-ext/../ruby-bson/changelog.Debian.gz
/usr/share/doc/ruby-bson-ext/../ruby-bson/changelog.Debian.gz