Fix found issues

tests/test_app/TestApp/Model/Entity/NonExtending.php

@@ -35,7 +35,7 @@ class NonExtending implements EntityInterface
         }
 
         if ($options['markNew'] !== null) {
-            $this->isNew();
+            $this->setNew($options['markNew']);
         }
 
         if (!empty($options['source'])) {

tests/test_app/templates/Pages/home.php

@@ -81,7 +81,7 @@ if (file_exists(APP . 'Config/datasources.php')): ?>
 <?php endif; ?>
 
 <p>
-<?php if (Plugin::loaded()): ?>
+<?php if (Plugin::isLoaded('DebugKit')): ?>
     <span class="notice success">DebugKit plugin is present</span>
 <?php else: ?>
     <span class="notice">';