Bump haskell-actions/run-fourmolu from 8 to 9

Bumps [haskell-actions/run-fourmolu](https://github.com/haskell-actions/run-fourmolu) from 8 to 9.
- [Release notes](https://github.com/haskell-actions/run-fourmolu/releases)
- [Changelog](https://github.com/haskell-actions/run-fourmolu/blob/master/CHANGELOG.md)
- [Commits](https://github.com/haskell-actions/run-fourmolu/compare/v8...v9

)

---
updated-dependencies:
- dependency-name: haskell-actions/run-fourmolu
  dependency-type: direct:production
  update-type: version-update:semver-major
...

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