Add 3.11 as supported env

Author: pgleeson

docs/sphinx/source/api/Contributors.md

@@ -3,7 +3,7 @@
 # Modelspec contributors
 
 This page list names and Github profiles of contributors to Modelspec, listed in no particular order.
-This page is generated periodically, most recently on 2023-11-22.
+This page is generated periodically, most recently on 2023-12-13.
 
 - Padraig Gleeson ([@pgleeson](https://github.com/pgleeson))
 - Manifest Chakalov  ([@mqnifestkelvin](https://github.com/mqnifestkelvin))

setup.cfg

@@ -26,6 +26,7 @@ classifiers =
     Programming Language :: Python :: 3.8
     Programming Language :: Python :: 3.9
     Programming Language :: Python :: 3.10
+    Programming Language :: Python :: 3.11
     Topic :: Scientific/Engineering
     Topic :: Software Development
     Typing :: Typed