Update Python versions tested on Github actions

.github/workflows/test.yml

@@ -7,7 +7,7 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        python-version: [ 3.6, 3.7, 3.8, 3.9, ]
+        python-version: [ "3.7", "3.8", "3.9", "3.10", "3.11", "3.12" ]
     steps:
       - uses: actions/checkout@v2