tileRectsIds populated as `[[null]]`

[Trouv]

Hello, one of my users ran into an issue where the new tileRectsIds field is being populated as [[null], [null]]: https://github.com/Trouv/bevy_ecs_ldtk/issues/300

However, the quicktype-generated rust module seems to believe that it cannot be null (the type is Vec<Vec<i64>> not Vec<Vec<Option<i64>>> I'm not sure about steps to reproduce this, but thought I'd post this in case the bug is obvious. I don't know whether the null is valid but the quicktype isn't, or if the null is invalid and the quicktype is correct?