Bump vimeo/psalm from 4.20.0 to 4.21.0

Bumps [vimeo/psalm](https://github.com/vimeo/psalm) from 4.20.0 to 4.21.0.
- [Release notes](https://github.com/vimeo/psalm/releases)
- [Commits](https://github.com/vimeo/psalm/compare/4.20.0...4.21.0

)

---
updated-dependencies:
- dependency-name: vimeo/psalm
  dependency-type: direct:development
  update-type: version-update:semver-minor
...

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