Updage github workflow for python 3.12.

Author: jtkiley

.github/workflows/test_notebooks.yml

@@ -13,7 +13,7 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        python-version: ["3.11"]
+        python-version: ["3.11", "3.12"]
 
     steps:
       - uses: actions/checkout@v3