Bump Python version up to 3.11 (#1404)

* Change workflow to test Python 3.11 instead of 3.8

* Update setup.py to use Python 3.11

Author: marcharper

.github/workflows/config.yml

@@ -14,7 +14,7 @@ jobs:
       max-parallel: 4
       matrix:
         os: [ubuntu-latest, windows-latest]
-        python-version: ["3.8", "3.9", "3.10"]
+        python-version: ["3.9", "3.10", "3.11"]
 
     steps:
     - uses: actions/checkout@v1

setup.py

@@ -29,9 +29,9 @@
     include_package_data=True,
     package_data={"": ["axelrod/data/*"]},
     classifiers=[
-        "Programming Language :: Python :: 3.8",
         "Programming Language :: Python :: 3.9",
         "Programming Language :: Python :: 3.10",
+        "Programming Language :: Python :: 3.11",
         "Programming Language :: Python :: 3 :: Only",
     ],
     python_requires=">=3.6",