tox: Update tested python versions

Keep 3.6 for openSUSE Leap/SLE. Use more recent versions available in
openSUSE Tumbleweed as well as ubuntu-latest.

.github/workflows/python-package.yaml

@@ -10,12 +10,8 @@ jobs:
       matrix:
         python-version:
         - '3.6'
-        - '3.7'
-        - '3.8'
-        - '3.9'
-        - '3.10'
         - '3.11'
-        - '3.12.0-alpha - 3.12.0'
+        - '3.12'
         include:
           - os: "ubuntu-latest"
           - os: "ubuntu-20.04"
@@ -60,7 +56,7 @@ jobs:
     - name: Set up Python
       uses: actions/setup-python@v3
       with:
-        python-version: '3.10'
+        python-version: '3.12'
     - name: Install dependencies
       run: python -m pip install tox
     - run: python -m tox -e ${{ matrix.test-type }}

tox.ini

@@ -4,7 +4,7 @@
 # and then run "tox" from this directory.
 
 [tox]
-envlist = flake8,black,doctests,py{36,37,38,39,310},cov
+envlist = flake8,black,doctests,py{36,311,312,313},cov
 deps = -rrequirements.txt
 skip_missing_interpreters = true