Don’t try to run pytest over Ribbit’s Python code

.github/workflows/pythonapp.yml

@@ -23,7 +23,7 @@ jobs:
         pip install -r requirements.txt
     - name: Test with pytest
       run: |
-        pytest -v --doctest-modules
+        pytest -v --doctest-modules --ignore alt/scheme/ribbit
     - name: Lint with flake8
       run: |
         pip install flake8