[web/autoform] fix regression introduced by #5758ba784ebd
The changes from cset 5758ba784ebd "[autoform] when building inlined-form view
for a relation, consider related entities intead of other views" lead to
an unexpected 'add new' link on creation of an entity with inlined form for
a relation of cardinality 1. To avoid this, we should consider formviews and not
existing relations when the entity is being created.
Closes #10860258
TACHES
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-- écrire objet stocke/manipule les données
-- extraire tests de chaîne de caractère
* utiliser sqlite
* écrire fonction prend chemin en argument et renvoie contenu
* extraire tests (chaîne de caractère) de spec
* utiliser yams pour schéma