OSIS-4114-dev add unittest for aca_year not required + text of EMPTY_LABEL
OSIS-4114-dev add unittest for aca_year not required + text of EMPTY_LABEL

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