Bump @oclif/plugin-plugins from 2.1.9 to 4.2.1

Bumps [@oclif/plugin-plugins](https://github.com/oclif/plugin-plugins) from 2.1.9 to 4.2.1.
- [Release notes](https://github.com/oclif/plugin-plugins/releases)
- [Changelog](https://github.com/oclif/plugin-plugins/blob/main/CHANGELOG.md)
- [Commits](oclif/plugin-plugins@2.1.9...4.2.1)

---
updated-dependencies:
- dependency-name: "@oclif/plugin-plugins"
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <[email protected]>