ci(deps)!: flake8 should work

Upgrade flake8 from 4 to 7. This upgrades pycodestyle. It also upgrades
pyflakes from 2 to 3.

BREAKING CHANGE: Upgrade the minimum Python version from 3.8.0 to 3.8.1

pyproject.toml

@@ -16,7 +16,7 @@ py-scrcpy = "scrcpy_ui:main"
 
 [tool.poetry.dependencies]
 # Should match the python versions in .github/workflows/ci.yml and publish.yml
-python = ">=3.8,<3.13"
+python = ">=3.8.1,<3.13"
 av = "^12"
 opencv-python = "^4.5.0"
 adbutils = "^1.0.8"
@@ -28,7 +28,7 @@ PySide6 = { version = "^6.0.0", optional = true }
 ui = ["PySide6"]
 
 [tool.poetry.dev-dependencies]
-flake8 = "^4.0.1"
+flake8 = "^7"
 isort = "*"
 black = "^22.3.0"
 pytest = "^7.1.2"