Bump webpack from 5.91.0 to 5.94.0 in /admin/discourse-sidebar (#525)

Bumps [webpack](https://github.com/webpack/webpack) from 5.91.0 to 5.94.0.
- [Release notes](https://github.com/webpack/webpack/releases)
- [Commits](webpack/webpack@v5.91.0...v5.94.0)

---
updated-dependencies:
- dependency-name: webpack
  dependency-type: indirect
...

Signed-off-by: dependabot[bot] <[email protected]>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>