docs: fixed constructor in add fulfillment provider (#3966)

Fixed the constructor in add fulfillment provider to remove the super parameters.

Closes #3947

docs/content/modules/carts-and-checkout/backend/add-fulfillment-provider.md

@@ -80,7 +80,7 @@ For example:
 class MyFulfillmentService extends FulfillmentService {
   // ...
   constructor(container, options) {
-    super(container)
+    super()
     // you can access options here
   }
 }