mgr/dashboard: bump prettier in /src/pybind/mgr/dashboard/frontend

Bumps [prettier](https://github.com/prettier/prettier) from 2.1.2 to 3.4.2.
- [Release notes](https://github.com/prettier/prettier/releases)
- [Changelog](https://github.com/prettier/prettier/blob/main/CHANGELOG.md)
- [Commits](prettier/prettier@2.1.2...3.4.2)

---
updated-dependencies:
- dependency-name: prettier
  dependency-type: direct:development
  update-type: version-update:semver-major
...

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