/usr/share/doc/libosgearthsymbology3/changelog.Debian.gz is in libosgearthsymbology3 2.5.0+dfsg-8build1.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/share/doc/libosgearthsymbology3/../libosgearth3/changelog.Debian.gz