/usr/lib/x86_64-linux-gnu/libignition-fuel_tools1.so is in libignition-fuel-tools1-dev 1.0.0+dfsg4-4.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/lib/x86_64-linux-gnu/libignition-fuel_tools1.so.1