Bump lib/nighres from 7293c36 to 31c60e3

Bumps [lib/nighres](https://github.com/nighres/nighres) from `7293c36` to `31c60e3`.
- [Release notes](https://github.com/nighres/nighres/releases)
- [Commits](nighres/nighres@7293c36...31c60e3)

---
updated-dependencies:
- dependency-name: lib/nighres
  dependency-type: direct:production
...

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