🧪 Test again python 3.12 (#19)

Author: chrisjsewell

.github/workflows/ci.yaml

@@ -29,7 +29,7 @@ jobs:
         sphinx-version: ["6.0", "7.0"]
         include:
           - os: "ubuntu-latest"
-            python-version: "3.11"
+            python-version: "3.12"
             sphinx-version: "8.0"
           - os: "windows-latest"
             python-version: "3.8"