/usr/lib/x86_64-linux-gnu/librabbitmq.so.4 is in librabbitmq4 0.8.0-1+b3.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/lib/x86_64-linux-gnu/librabbitmq.so.4.2.0
/usr/lib/x86_64-linux-gnu/librabbitmq.so.4.2.0