remove unsupported python from the pipeline

Author: RonnyPfannschmidt

.github/workflows/python-tests.yml

@@ -20,7 +20,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        python_version: [ '3.6', '3.7', '3.8', '3.9', '3.10', 'pypy-3.6' ]
+        python_version: ['3.7', '3.8', '3.9', '3.10', '3.11', 'pypy-3.8' ]
         os: [windows-latest, ubuntu-latest] #, macos-latest]
         include:
         - os: windows-latest