chore(deps): update dependency flake8 to v7

Author: renovate[bot]

pyproject.toml

@@ -28,7 +28,7 @@ rdflib = "^6.0.0"
 [tool.poetry.dev-dependencies]
 pytest = "^7.0"
 tox = "^3.20.1"
-flake8 = "^4.0.0"
+flake8 = "^7.0.0"
 autopep8 = "^1.5.4"
 
 [tool.poetry.scripts]