/usr/lib/x86_64-linux-gnu/libpulse.so is in libpulse-dev 10.0-1+deb9u1.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/lib/x86_64-linux-gnu/libpulse.so.0.20.1
/usr/lib/x86_64-linux-gnu/libpulse.so.0.20.1