Update state-providers.md

[gonzaloalonsod]

Return JsonResponse

[gonzaloalonsod]

This change doesn't look good to me.

The provider must return an object that will be handled by the serializer, not a HTTP response.

"Returns an empty DTO, does not serialize the object. Should it be explicit when serializing? Do you have an example?"

[dunglas]

This shouldn't return an empty object. The serialization is done automatically, no need to do it explicitly. This example should work.