Add flake8

Author: itepifanio

pyproject.toml

@@ -34,6 +34,7 @@ babel = ">=2.9.1"
 sphinx = ">=4.0.2"
 pytest = ">=6.0.0"
 pytest-html = ">=3.0.0"
+flake8 = ">=6.1.0"
 
 [build-system]
 requires = ["poetry-core"]