Merge pull request #3570 from tornadoweb/dependabot/pip/filelock-3.20.3

build(deps): bump filelock from 3.20.1 to 3.20.3

Author: bdarnell

requirements.txt

@@ -32,7 +32,7 @@ docutils==0.21.2
     # via
     #   sphinx
     #   sphinx-rtd-theme
-filelock==3.20.1
+filelock==3.20.3
     # via
     #   tox
     #   virtualenv