delete method
Implementation
@override
FutureOr<DeleteDbResult> delete(Access access) {
if (access.identifier == null) {
throw BadRequests();
}
if (data[access.collection]?[access.identifier!] == null) {
return DeleteDbResult(exists: false);
} else {
data[access.collection]!.remove(access.identifier);
return DeleteDbResult(exists: true);
}
}