/usr/lib/x86_64-linux-gnu/libspice-client-gtk-3.0.so is in libspice-client-gtk-3.0-dev 0.33-3.3+deb9u1.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/lib/x86_64-linux-gnu/libspice-client-gtk-3.0.so.5.0.0