add python 3.11 to pypi metadata

setup.py

@@ -285,6 +285,7 @@ setup(
         'Programming Language :: Python :: 3.8',
         'Programming Language :: Python :: 3.9',
         'Programming Language :: Python :: 3.10',
+        'Programming Language :: Python :: 3.11',
         'Topic :: Security :: Cryptography',
         'Topic :: System :: Archiving :: Backup',
     ],