update test workflow

Author: peterrrock2

.github/workflows/tests.yaml

@@ -7,7 +7,7 @@ jobs:
     runs-on: ${{ matrix.os }}
     strategy:
       matrix:
-        python-version: [3.9, '3.10', 3.11, 3.12]
+        python-version: [3.11, 3.12]
         os: [ubuntu-latest, macOS-latest]
 
     steps: