build(deps-dev): bump webpack in /src/handler/webui

Bumps [webpack](https://github.com/webpack/webpack) from 5.90.1 to 5.91.0.
- [Release notes](https://github.com/webpack/webpack/releases)
- [Commits](webpack/webpack@v5.90.1...v5.91.0)

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

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