remove all Model.query.get() [tests not OK] WIP

app/api/justificatifs.py

app/but/change_refcomp.py

app/comp/moy_ue.py

app/models/assiduites.py

app/scodoc/sco_formsemestre_inscriptions.py

app/scodoc/sco_inscr_passage.py

app/scodoc/sco_pv_dict.py

app/scodoc/sco_saisie_notes.py

app/scodoc/sco_ue_external.py

app/tables/liste_assiduites.py

app/views/assiduites.py

app/views/scolar.py

app/views/user_board.py

tests/unit/test_sco_basic.py