Bump tornado from 6.4.1 to 6.4.2 in /tests/functional_tests (#56)

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>

tests/functional_tests/requirements.txt

@@ -1,4 +1,4 @@
 numpy==1.22.4
 python-dotenv==0.21.0
 scikit-learn==1.1.2
-tornado==6.4.1
+tornado==6.4.2