There's a closed pull request on the void-packages repository

nicotine+: update to 2.1.2
https://github.com/void-linux/void-packages/pull/25229

Description:
Nicotine+ switched from `mutagen` to `pytaglib`. The latter is not in the repos yet.
I am not sure whether `GPL-3.0-only` or `GPL-3.0-or-later` is right for `pytaglib`

Tested on x86_64-musl