[ci] Bump typescript from 5.2.2 to 5.9.3 in /load-tester

Bumps [typescript](https://github.com/microsoft/TypeScript) from 5.2.2 to 5.9.3.
- [Release notes](https://github.com/microsoft/TypeScript/releases)
- [Commits](microsoft/TypeScript@v5.2.2...v5.9.3)

---
updated-dependencies:
- dependency-name: typescript
  dependency-version: 5.9.3
  dependency-type: direct:development
  update-type: version-update:semver-minor
...

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

Author: dependabot[bot]