Make functions and tests compatible with laravel 7

Date serialization changes
Laravel 7 uses a new date serialization format when using the toArray or toJson method on Eloquent models. To format dates for serialization, the framework now uses Carbon's toJSON method, which produces an ISO-8601
https://laravel.com/docs/7.x/upgrade#date-serialization
 laravel_7_comptability

$model->getOriginal() was moved to getRawOriginal method See https://laravel.com/docs/7.x/upgrade#factory-types