Remove final from the Zone's form component (#16270)

| Q               | A
|-----------------|-----
| Branch?         | bootstrap-admin-panel <!-- see the comment below -->
| Bug fix?        | no
| New feature?    | no
| BC breaks?      | no
| License         | MIT

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To be consisted with the rest of changes in
#16221

src/Sylius/Bundle/AdminBundle/Twig/Component/Zone/FormComponent.php

@@ -23,7 +23,7 @@
 use Symfony\UX\LiveComponent\LiveCollectionTrait;
 
 #[AsLiveComponent]
-final class FormComponent
+class FormComponent
 {
     use DefaultActionTrait;
     use HookableLiveComponentTrait;