Fix typito in `live-current-pack-dir` docstring.

*typito* _n._ - a tiny typo, often trivial.
> If users of open-source libraries correct *typitos* and other
> little errors themselves, the creators and maintainers are free
> to spend their creative energies elsewhere.
Merge pull request #110 from MerelyAPseudonym/patch-2

Fix typito in `live-current-pack-dir` docstring.