Marked the code field of a Menu as required (as defined in db table)

Author: Ben Verbist

src/Resources/MenuResource.php

@@ -73,7 +73,7 @@ public static function form(Form $form): Form
                 ->maxLength(255)
                 ->helperText(flexiblePagesTrans('menus.form.name_help')),
 
-            CodeField::create()
+            CodeField::create(true)
                 ->helperText(flexiblePagesTrans('menus.form.code_help')),
         ];