added Python versions up to 3.12

.github/workflows/core-tests.yml

@@ -10,7 +10,7 @@ jobs:
       matrix:
         # This range ensures coding standard does not conflict with 
         #  changes in newer Pythons
-        python-version: [3.7, 3.8, 3.9, "3.10"]
+        python-version: [3.7, 3.8, 3.9, "3.10", "3.11", "3.12"]
 
     steps:
     - uses: actions/checkout@v3