withConverter method
Applies a custom data converter to this DocumentReference, allowing you
to use your own custom model objects with Firestore. When you call
set(), get(), etc. on the returned DocumentReference instance, the
provided converter will convert between Firestore data of type
NewDbModelType and your custom type NewAppModelType.
@param converter Converts objects to and from Firestore. Passing in
null removes the current converter.
@return A DocumentReference
Implementation
external DocumentReference withConverter(FirestoreDataConverter? converter);