Links not passed

When a tracker contains a link, the field is reported as:

{"field_id":65523,"label":"Liens Artéfacts/Versions","type":"art_link","value":null,"values":null,"file_descriptions":null}

The reason is links are stored in a links attribute.

{"field_id":65523,"label":"Liens Art\u00e9facts\/Versions","type":"art_link","links":[{"id":195184,"uri":"artifacts\/195184","tracker":{"id":1984,"uri":"trackers\/1984","label":"FT","color":"lake-placid-blue","project":{"id":241,"uri":"projects\/241","label":"SRSA-IP","icon":"\ud83d\udeeb"}},"type":null}],"reverse_links":[]},```