fix qtapp
- import handling of
enable_ewokstest_category.widget_discoverymightnot be defined - improve robustness of
qtapp_context:ensure_qtappmight return None in case_APPalready exists.
Edited by payno
enable_ewokstest_category. widget_discovery mightnot be definedqtapp_context: ensure_qtapp might return None in case _APP already exists.