fix unit tests

tests/Unit/Service/Export/BaseExporterTest.php

@@ -42,6 +42,7 @@ class BaseExporterTest extends TestCase
     private MockObject | EntityManagerInterface $entityManager;
     private MockObject | LoggerInterface $logger;
     private MockObject | FileManager $fileManager;
+    private MockObject | FileUtils $fileUtils;
 
     public function setUp(): void {
         $this->accessRepository = $this->getMockBuilder(AccessRepository::class)->disableOriginalConstructor()->getMock();