build(deps): bump tornado from 6.4.1 to 6.4.2 in /docs (#24)

Bumps [tornado](https://github.com/tornadoweb/tornado) from 6.4.1 to 6.4.2.
- [Changelog](https://github.com/tornadoweb/tornado/blob/v6.4.2/docs/releases.rst)
- [Commits](tornadoweb/tornado@v6.4.1...v6.4.2)

---
updated-dependencies:
- dependency-name: tornado
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <[email protected]>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

docs/requirements.txt

@@ -26,7 +26,7 @@ regex==2021.8.3
 requests==2.32.0
 six==1.16.0
 toml==0.10.2
-tornado==6.4.1
+tornado==6.4.2
 tqdm==4.66.3
 ujson==5.4.0
 urllib3==1.26.19