chore(deps-dev): bump webpack-cli in /build/frontend-legacy

Bumps [webpack-cli](https://github.com/webpack/webpack-cli) from 6.0.1 to 7.0.3.
- [Release notes](https://github.com/webpack/webpack-cli/releases)
- [Changelog](https://github.com/webpack/webpack-cli/blob/main/CHANGELOG.md)
- [Commits](https://github.com/webpack/webpack-cli/compare/webpack-cli@6.0.1...webpack-cli@7.0.3)

---
updated-dependencies:
- dependency-name: webpack-cli
  dependency-version: 7.0.3
  dependency-type: direct:development
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]