Remove python 3.9 support

Author: MDUYN

.github/workflows/test.yml

@@ -41,7 +41,7 @@ jobs:
       fail-fast: true
       matrix:
         os: [ "ubuntu-latest", "macos-latest" ]
-        python-version: ["3.10", "3.11" ]
+        python-version: [ "3.10", "3.11" ]
     defaults:
       run:
         shell: bash