/usr/share/doc/nova-cells/changelog.Debian.gz is in nova-cells 2:13.0.0-0ubuntu2.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/share/doc/nova-cells/../python-nova/changelog.Debian.gz
/usr/share/doc/nova-cells/../python-nova/changelog.Debian.gz