chore(deps-dev): bump xenon from 0.8.0 to 0.9.0

Bumps [xenon](https://github.com/rubik/xenon) from 0.8.0 to 0.9.0.
- [Release notes](https://github.com/rubik/xenon/releases)
- [Changelog](https://github.com/rubik/xenon/blob/master/CHANGELOG)
- [Commits](rubik/xenon@v0.8.0...v0.9.0)

---
updated-dependencies:
- dependency-name: xenon
  dependency-type: direct:development
  update-type: version-update:semver-minor
...

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

pyproject.toml

@@ -18,7 +18,7 @@ pytest-mypy = "^0.9.1"
 toml = "^0.10.2"
 types-toml = "^0.10.4"
 twine = "^3.8.0"
-xenon = "^0.8.0"
+xenon = "^0.9.0"
 radon = "^5.1.0"
 
 [tool.poetry.scripts]