vlib/v/checker/tests/orm_fkey_has_pkey.vv:5:2: error: ORM: a struct that has a field that holds an array must have a primary key
    3 | struct Person {
    4 |     id    int
    5 |     child []Child @[fkey: 'person_id']
      |     ~~~~~~~~~~~~~
    6 | }
    7 |