FIX static tests, missing declare(strict_types=1)

Author: phoenix128

lib/internal/Magento/Framework/Webapi/Test/Unit/ServiceInputProcessor/SimpleConstructor.php

@@ -3,6 +3,8 @@
  * Copyright © Magento, Inc. All rights reserved.
  * See COPYING.txt for license details.
  */
+declare(strict_types=1);
+
 namespace Magento\Framework\Webapi\Test\Unit\ServiceInputProcessor;
 
 class SimpleConstructor