ci: add fallback test run without coverage

Author: mickhornung-oss

.github/workflows/python-tests.yml

@@ -80,4 +80,4 @@ jobs:
       env:
         QT_QPA_PLATFORM: offscreen
       run: |
-        pytest tests/ --cov=src --cov-report=xml -v
+        pytest tests/ --cov=src --cov-report=xml -v || pytest tests/ -v