Update supported python versions

Author: oohlaf

setup.py

@@ -45,6 +45,9 @@
           "Programming Language :: Python :: 3.6",
           "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",
           "Topic :: Software Development :: Version Control",
           "Topic :: System :: Systems Administration",
           "Topic :: Utilities"