setup.py: add classifiers for Python 3.11 and 3.12

For what it's worth, I'm using this on Python 3.12.

Author: alanorth

setup.py

@@ -22,6 +22,8 @@
         "Programming Language :: Python :: 3.8",
         "Programming Language :: Python :: 3.9",
         "Programming Language :: Python :: 3.10",
+        "Programming Language :: Python :: 3.11",
+        "Programming Language :: Python :: 3.12",
         "License :: OSI Approved :: BSD License",
         "Operating System :: OS Independent",
     ],