/usr/lib/libgtkspell3-3.so is in libgtkspell3-3-dev 3.0.4-1.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/lib/libgtkspell3-3.so.0.1.0
/usr/lib/libgtkspell3-3.so.0.1.0