tools: bump piscina from 5.1.4 to 5.2.0 in /tools/doc

Bumps [piscina](https://github.com/piscinajs/piscina) from 5.1.4 to 5.2.0.
- [Release notes](https://github.com/piscinajs/piscina/releases)
- [Changelog](https://github.com/piscinajs/piscina/blob/v5.2.0/CHANGELOG.md)
- [Commits](piscinajs/piscina@v5.1.4...v5.2.0)

---
updated-dependencies:
- dependency-name: piscina
  dependency-version: 5.2.0
  dependency-type: indirect
...

Signed-off-by: dependabot[bot] <support@github.com>
PR-URL: #64002
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>

Author: dependabot[bot]