Bump reffy from 17.2.7 to 17.2.9

Bumps [reffy](https://github.com/w3c/reffy) from 17.2.7 to 17.2.9.
- [Changelog](https://github.com/w3c/reffy/blob/main/CHANGELOG.md)
- [Commits](https://github.com/w3c/reffy/commits)

---
updated-dependencies:
- dependency-name: reffy
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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