fix(reana-dev): classify error-throwing tests as failed (reanahub#817)

If a workflow throws an error while being tested (in run-example), it is now classified as failing

reana/reana_dev/run.py

@@ -561,12 +561,12 @@ def _get_test_matrix_summary() -> str:
                                 component,
                                 return_output=True,
                             )
-
                             if re.findall(r".*failed$", tests, re.MULTILINE):
                                 run_statistics["failed"].append(workflow_name)
                             else:
                                 run_statistics["passed"].append(workflow_name)
                         except SystemExit:
+                            run_statistics["failed"].append(workflow_name)
                             display_message(
                                 f"Workflow {workflow_name} has no tests.", component
                             )