Bump qs from 6.13.1 to 6.15.2 in /extensions/ql-vscode

Bumps [qs](https://github.com/ljharb/qs) from 6.13.1 to 6.15.2.
- [Changelog](https://github.com/ljharb/qs/blob/main/CHANGELOG.md)
- [Commits](ljharb/qs@v6.13.1...v6.15.2)

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

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

Author: dependabot[bot]