Update tox requirement from 4.16.0 to 4.20.0

Updates the requirements on [tox](https://github.com/tox-dev/tox) to permit the latest version.
- [Release notes](https://github.com/tox-dev/tox/releases)
- [Changelog](https://github.com/tox-dev/tox/blob/main/docs/changelog.rst)
- [Commits](tox-dev/tox@4.16.0...4.20.0)

---
updated-dependencies:
- dependency-name: tox
  dependency-type: direct:development
...

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

pyproject.toml

@@ -42,7 +42,7 @@ tabulate = "0.8.10"
 
 
 [tool.poetry.group.dev.dependencies]
-tox = "4.16.0"
+tox = "4.20.0"
 
 
 [tool.poetry.group.test.dependencies]