add helper trait to build filter form

src/Controller/DatagridControllerHelper.php

@@ -0,0 +1,16 @@
+<?php
+
+namespace Kibatic\DatagridBundle\Controller;
+
+use Symfony\Component\Form\FormBuilderInterface;
+
+trait DatagridControllerHelper
+{
+    public function createFilterFormBuilder(string $name = '', string $method = 'GET', bool $csrfProtection = false): FormBuilderInterface
+    {
+        return $this->container->get('form.factory')->createNamedBuilder($name, options: [
+            'method' => $method,
+            'csrf_protection' => $csrfProtection,
+        ]);
+    }
+}