chore(deps): Bump webdav from 5.8.0 to 5.9.0 in /build/frontend-legacy

Bumps [webdav](https://github.com/perry-mitchell/webdav-client) from 5.8.0 to 5.9.0.
- [Changelog](https://github.com/perry-mitchell/webdav-client/blob/master/CHANGELOG.md)
- [Commits](perry-mitchell/webdav-client@v5.8.0...v5.9.0)

---
updated-dependencies:
- dependency-name: webdav
  dependency-version: 5.9.0
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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Author: dependabot[bot]