Bump tornado from 6.1 to 6.3.2

Bumps [tornado](https://github.com/tornadoweb/tornado) from 6.1 to 6.3.2.
- [Changelog](https://github.com/tornadoweb/tornado/blob/master/docs/releases.rst)
- [Commits](tornadoweb/tornado@v6.1.0...v6.3.2)

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

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

requirements.txt

@@ -24,7 +24,7 @@ ruamel.yaml==0.16.12
 ruamel.yaml.clib==0.2.2
 six==1.12.0
 termcolor==1.1.0
-tornado==6.1
+tornado==6.3.2
 tqdm==4.58.0
 typing-extensions==3.7.4.3
 zipp==3.4.0