feat(ci): add 3.12 for testing matrix

Author: Christian Grabowski

.github/workflows/ci.yml

@@ -38,6 +38,7 @@ jobs:
           - "3.8"
           - "3.9"
           - "3.10"
+          - "3.12"
     steps:
     - name: Repository checkout
       uses: actions/checkout@v3