Bump tornado from 6.4.1 to 6.4.2 in /tfx/tools/docker (#7641)

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>

tfx/tools/docker/requirements.txt

@@ -326,7 +326,7 @@ tinycss2==1.3.0
 toml==0.10.2
 tomli==2.0.2
 toolz==1.0.0
-tornado==6.4.1
+tornado==6.4.2
 tqdm==4.66.5
 traitlets==5.14.3
 types-python-dateutil==2.9.0.20241003