Update flake8 config.

Author: domdfcoding

.github/workflows/flake8.yml

@@ -35,7 +35,7 @@ jobs:
         if: steps.changes.outputs.code == 'true'
         uses: "actions/setup-python@v2"
         with:
-          python-version: "3.6"
+          python-version: "3.8"
 
       - name: Install dependencies 🔧
         if: steps.changes.outputs.code == 'true'

tox.ini

@@ -159,20 +159,20 @@ filterwarnings =
     ignore:can't resolve package from __spec__ or __package__, falling back on __name__ and __path__:ImportWarning
 
 [testenv:lint]
-basepython = python3.6
+basepython = python3.8
 changedir = {toxinidir}
 ignore_errors = True
 skip_install = False
 deps =
-    flake8>=3.8.2
+    flake8>=3.8.2,<5
     flake8-2020>=1.6.0
     flake8-builtins>=1.5.3
     flake8-docstrings>=1.5.0
     flake8-dunder-all>=0.1.1
     flake8-encodings>=0.1.0
     flake8-github-actions>=0.1.0
-    flake8-noqa>=1.1.0
-    flake8-pyi>=20.10.0
+    flake8-noqa>=1.1.0,<=1.2.2
+    flake8-pyi>=20.10.0,<=22.8.0
     flake8-pytest-style>=1.3.0
     flake8-quotes>=3.3.0
     flake8-slots>=0.1.0
@@ -182,7 +182,8 @@ deps =
     git+https://github.com/domdfcoding/flake8-rst-docstrings-sphinx.git
     git+https://github.com/domdfcoding/flake8-rst-docstrings.git
     git+https://github.com/python-formate/flake8-unused-arguments.git@magic-methods
+    git+https://github.com/python-formate/flake8-missing-annotations.git
     pydocstyle>=6.0.0
     pygments>=2.7.1
     importlib_metadata<4.5.0; python_version<'3.8'
-commands = python3 -m flake8_rst_docstrings_sphinx flake8_github_actions tests --allow-toolbox --extend-exclude bad_code.py {posargs} {posargs}
+commands = python3 -m flake8_rst_docstrings_sphinx flake8_github_actions tests --allow-toolbox --extend-exclude bad_code.py {posargs}