add 3.13 tests

Author: marcelkroeker

.github/workflows/test.yml

@@ -9,7 +9,7 @@ jobs:
 
     strategy:
       matrix:
-        python-version: ["3.8", "3.9", "3.10", "3.11", "3.12"]
+        python-version: ["3.8", "3.9", "3.10", "3.11", "3.12", "3.13"]
 
     steps:
       #----------------------------------------------