Bump filelock from 3.16.1 to 3.20.1 in /requirements

Bumps [filelock](https://github.com/tox-dev/py-filelock) from 3.16.1 to 3.20.1.
- [Release notes](https://github.com/tox-dev/py-filelock/releases)
- [Changelog](https://github.com/tox-dev/filelock/blob/main/docs/changelog.rst)
- [Commits](tox-dev/filelock@3.16.1...3.20.1)

---
updated-dependencies:
- dependency-name: filelock
  dependency-version: 3.20.1
  dependency-type: indirect
...

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

requirements/release.txt

@@ -16,7 +16,7 @@ charset-normalizer==3.4.0
     # via requests
 distlib==0.3.9
     # via virtualenv
-filelock==3.16.1
+filelock==3.20.1
     # via
     #   python-tools-scripts
     #   virtualenv