docs: list python versions

Author: waketzheng

pyproject.toml

@@ -22,6 +22,12 @@ classifiers = [
     "Topic :: Internet :: WWW/HTTP :: Dynamic Content :: CGI Tools/Libraries",
     "Topic :: Internet :: WWW/HTTP :: WSGI",
     "Programming Language :: Python :: 3",
+    '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 :: 3.13',
 ]
 
 [project.urls]