fix action btn widger

kernel/widgets/ActionButtonWidget.php

@@ -6,11 +6,12 @@ use kernel\Widget;
 
 class ActionButtonWidget extends Widget
 {
-    public function run(): void
+    public function run(): string
     {
         $label = $this->data['label'];
         $btn_type = $this->data['btn_type'];
         $url = $this->data['url'];
-        $this->cgView->render('/action_button.php', ['label' => $label, 'btn_type' => $btn_type, 'url' => $url]);
+
+        return $this->cgView->fetch('/action_button.php', ['label' => $label, 'btn_type' => $btn_type, 'url' => $url]);
     }
 }