tests: fix counting selenium failures

1b1dbf60 (tests: also consider python unittest failures in
functional tests, 2021-06-16) was not counting properly the cases
where we have selenium failures. In that case we only want to count
selenium failures, if we add with the python failures from
status_dict, we report one extra failures.

The correct approach is to count selenium failures if any and otherwise
count python failures
Co-authored-by: Vincent Pelletier <vincent@nexedi.com>

tests/__init__.py

@@ -161,7 +161,7 @@ class ERP5(_ERP5):
     if search:
       group_dict = search.groupdict()
       status_dict['failure_count'] = int(group_dict['failures']) \
-          + int(status_dict.get('failure_count', 0))
+          or int(status_dict.get('failure_count', 0))
       status_dict['test_count'] = int(group_dict['total'])
       status_dict['skip_count'] = int(group_dict['expected_failure'])
     return status_dict