ENH: Add Python 3.12 to CI testing

Author: thewtex

.github/workflows/notebook-test.yml

@@ -8,7 +8,7 @@ jobs:
     name: Test notebooks with nbmake
     strategy:
       matrix:
-        python-version: ['3.8', '3.9', '3.10', '3.11']
+        python-version: ['3.8', '3.9', '3.10', '3.11', '3.12']
     steps:
       - uses: actions/checkout@v3
         with: