Apply fixes from StyleCI

Author: StyleCIBot

migrations/m250707_103609_tree.php

@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 use yii\db\Migration;
 
 class m250707_103609_tree extends Migration
@@ -41,5 +43,4 @@ public function safeDown()
     {
         $this->dropTable('{{%tree}}');
     }
-
 }

migrations/m250707_104009_multiple_tree.php

@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 use yii\db\Migration;
 
 class m250707_104009_multiple_tree extends Migration

tests/support/stub/EchoMigrateController.php

@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 namespace yii2\extensions\nestedsets\tests\support\stub;
 
 use yii\console\controllers\MigrateController;