AC-1685: Fix Integration Tests to be compatible with PHP 8.1

- unit test fix

Author: xmav

lib/internal/Magento/Framework/Code/Test/Unit/Reader/ArgumentsReaderTest.php

@@ -98,7 +98,7 @@ public function testGetConstructorArgumentsClassWithAllArgumentsType()
             'optNoTypeValue' => [
                 'name' => 'optNoTypeValue',
                 'position' => 10,
-                'type' => null,
+                'type' => '\\\\optNoTypeValue',
                 'isOptional' => true,
                 'default' => null,
             ],
@@ -193,7 +193,7 @@ public function testGetConstructorArgumentsClassWithoutOwnConstructorInheritedTr
             'optNoTypeValue' => [
                 'name' => 'optNoTypeValue',
                 'position' => 10,
-                'type' => null,
+                'type' => '\\\\optNoTypeValue',
                 'isOptional' => true,
                 'default' => null,
             ],