修改已经弃用的classname

vendor/iron/generators/model/default/model.php

@@ -112,7 +112,7 @@ class <?= $className ?> extends <?= '\\' . ltrim($generator->baseClass, '\\') .
     {
         return [
             [
-                'class' => TimestampBehavior::className(),
+                'class' => TimestampBehavior::class,
                 'createdAtAttribute' => 'created_at',
                 'updatedAtAttribute' => 'updated_at',
                 'value' => function() {