OSIS-3513 correct test for duplicated AcademicCalendar in TestDelete
OSIS-3513 correct test for duplicated AcademicCalendar in TestDelete

uclouvain/osis,uclouvain/osis,uclouvain/OSIS-Louvain,uclouvain/osis,uclouvain/OSIS-Louvain,uclouvain/OSIS-Louvain,uclouvain/osis