Scott Tester

There appears to be an infinite recursive loop causing a segmentation fault. From vdebug: ``` [0] common\models\Child->getParent @ /home/example/example/vendor/jlorente/yii2-activerecord-inheritance/src/ActiveRecordInheritanceTrait.php:94 [1] common\models\Child->__isset @ /home/example/example/vendor/jlorente/yii2-activerecord-inheritance/src/ActiveRecordInheritanceTrait.php:176 [2] common\models\Child->offsetExists @ /home/example/example/vendor/yiisoft/yii2/db/BaseActiveRecord.php:1225 [3] yii\db\ActiveQuery->filterByModels @...

Thanks tjdraper! Fixes the 404 for me. I support this PR.