Require python >= 3.9

Major distribution ship at least 3.9 and this will allow us to type with
dict, list, tuple instead of typing.Dict, List, Tuple etc.

.github/workflows/tox.yml

@@ -24,7 +24,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        python-version: ["3.8", "3.9", "3.10", "3.11"]
+        python-version: ["3.9", "3.10", "3.11"]
     steps:
     - uses: actions/checkout@v3
     - name: Set up Python ${{ matrix.python-version }}

setup.cfg

@@ -18,16 +18,16 @@ classifiers =
     Programming Language :: Python
     Programming Language :: Python :: 3
     Programming Language :: Python :: 3 :: Only
-    Programming Language :: Python :: 3.8
     Programming Language :: Python :: 3.9
     Programming Language :: Python :: 3.10
+    Programming Language :: Python :: 3.11
     Topic :: Software Development :: Testing
     Topic :: System :: Systems Administration
     Framework :: Pytest
 
 [options]
 use_scm_version = True
-python_requires = >=3.8
+python_requires = >=3.9
 packages = find:
 setup_requires =
     setuptools_scm