⬆️ Update isort requirement from ^4.3.21 to ^5.8.0

Updates the requirements on [isort](https://github.com/pycqa/isort) to permit the latest version.
- [Release notes](https://github.com/pycqa/isort/releases)
- [Changelog](https://github.com/PyCQA/isort/blob/main/CHANGELOG.md)
- [Commits](PyCQA/isort@4.3.21...5.8.0)

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

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

pyproject.toml

@@ -12,7 +12,7 @@ pytest = "^5.4.1"
 
 [tool.poetry.dev-dependencies]
 black = "^19.10b0"
-isort = "^4.3.21"
+isort = "^5.8.0"
 autoflake = "^1.3.1"
 mypy = "^0.770"