Update classifiers

Author: frenzymadness

setup.cfg

@@ -17,6 +17,9 @@ classifiers =
     Programming Language :: Python :: 3.7
     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
     Programming Language :: Python :: Implementation :: CPython
     License :: OSI Approved :: MIT License
     Operating System :: POSIX :: Linux