Serialization issue with frankenphp worker mode due to normalizer cache

[julien-maurel]

API Platform version(s) affected: 4.3.1

Description
2 APIs:

• 1 : use DTO A as output
• 2 : use DTO B as output

DTO B has a property that is an array of DTO A

On non worker mode:

• call API 1 : ItemNormalizer is used on DTO A
• call API 2 : ObjectNormalizer is used on the array of DTO A

Difference is produce by AbstractItemNormalizer:115, on API 1 condition return true and on API 2 false

        if (($context['output']['class'] ?? null) === $class) {
            return true;
        }

On worker mode:

• call API 1 : ItemNormalizer is used on DTO A and result is set on serializer cache
• call API 2 : because previous call cache ItemNormalizer as true for DTO A in normalizer cache of serializer, ItemNormalizer is used again and produce this error
  ApiPlatform\Metadata\ResourceClassResolver::isResourceClass(): Argument #1 ($type) must be of type string, null given, called in vendor/api-platform/core/src/Serializer/AbstractItemNormalizer.php on line 461 because $context['resource_class'] is unset before serialization of the array of DTO A

Tested on jsonLD and json formats

[soyuka]

would you be able to try #7873 ?

[julien-maurel]

@soyuka yes it's ok for me, I had already test this change yesterday but no time to propose a PR.
Thanks