Bump webpack-cli from 4.8.0 to 4.9.0

Bumps [webpack-cli](https://github.com/webpack/webpack-cli) from 4.8.0 to 4.9.0.
- [Release notes](https://github.com/webpack/webpack-cli/releases)
- [Changelog](https://github.com/webpack/webpack-cli/blob/master/CHANGELOG.md)
- [Commits](https://github.com/webpack/webpack-cli/compare/webpack-cli@4.8.0...webpack-cli@4.9.0

)

---
updated-dependencies:
- dependency-name: webpack-cli
  dependency-type: direct:development
  update-type: version-update:semver-minor
...

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