Bump qs from 6.15.0 to 6.15.2 in /Themes (#14477)

Bumps [qs](https://github.com/ljharb/qs) from 6.15.0 to 6.15.2.
- [Changelog](https://github.com/ljharb/qs/blob/main/CHANGELOG.md)
- [Commits](ljharb/qs@v6.15.0...v6.15.2)

---
updated-dependencies:
- dependency-name: qs
  dependency-version: 6.15.2
  dependency-type: indirect
...

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
Co-authored-by: Sean McManus <seanmcm@microsoft.com>

Author: dependabot[bot]