Dropping 3.9 support

Author: glenrobson

.github/workflows/test.yml

@@ -11,7 +11,7 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        python-version: [ '3.9', '3.10', '3.11']
+        python-version: [ '3.10', '3.11']
     name: Python ${{ matrix.python-version }} sample
     steps:
       - uses: actions/checkout@v4