ZendDB does not enforce return types, so we need to handle possibility of strings.
ZendDB's AbstractTableGateway.php does not declare its return type (other than in its docBlock), but UserModel.php sets a return type of int with no validation or guarantee that that the table gateway has actually returned an int.
ZendDB does not enforce return types, so we need to handle possibility of strings.
https://github.com/ezimuel/zend-expressive-api/pull/3#issuecomment-388360022