/usr/share/doc/libaunit-doc/examples/liskov/tested_lib/testlib.gpr is in libaunit-doc 3.7.2-1.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/share/doc/libaunit-doc/examples/liskov/tested_lib/../../simple_test/tested_lib/testlib.gpr