ci: simplify pytest call and remove cov report generation on windows …

…runner because it's not used.

.github/workflows/windows_unit_tests.yml

@@ -42,4 +42,4 @@ jobs:
       - name: Test with pytest
         shell: cmd
         run: |
-          python -m pytest .  --cov=hnn_core hnn_core/tests/ --cov-report=xml
+          python -m pytest ./hnn_core/tests/