Add 3.12 classifier and tox configuration (#6503)

Author: nateprewitt

setup.py

@@ -112,6 +112,7 @@ def run_tests(self):
         "Programming Language :: Python :: 3.9",
         "Programming Language :: Python :: 3.10",
         "Programming Language :: Python :: 3.11",
+        "Programming Language :: Python :: 3.12",
         "Programming Language :: Python :: 3 :: Only",
         "Programming Language :: Python :: Implementation :: CPython",
         "Programming Language :: Python :: Implementation :: PyPy",

tox.ini

@@ -1,5 +1,5 @@
 [tox]
-envlist = py{37,38,39,310,311}-{default, use_chardet_on_py3}
+envlist = py{37,38,39,310,311,312}-{default, use_chardet_on_py3}
 
 [testenv]
 deps = -rrequirements-dev.txt