/usr/share/doc/libgnuradio-runtime3.7.11/changelog.Debian.gz is in libgnuradio-runtime3.7.11 3.7.11-10.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/share/doc/libgnuradio-runtime3.7.11/../libgnuradio-pmt3.7.11/changelog.Debian.gz