[bug][symfony] AnyType is not defined

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• Have you provided a full/minimal spec to reproduce the issue?
• Have you validated the input using an OpenAPI validator (example)?
• Have you tested with the latest master to confirm the issue still exists?
• Have you searched for related issues/PRs?
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Description

AnyType is not defined in symfony server generated code.
In some situations, schemas return any, this is handled in other languages where that is translated into something the language understands, examples:

• Java: Object
• C#: `Object
• Rust: serde_json:Value

However, this translation is not made for symfony, and the generators write AnyType in such situations, leading to type errors:
AnyType is not defined anywhere.

openapi-generator version

7.2.0

some_data:
      type: object
      additionalProperties: true

or

some_data:
      type: object
      additionalProperties: {}

when a request is made with some data , this exception is thrown by JMSSerializer in vendor/jms/metadata/src/MetadataFactory.php

curl --location --request POST 'http://localhost:8000/myservice' \
--header 'Content-Type: application/json' \
--data-raw '{
  "some_data": {
    "additionalProp1": "string",
    "additionalProp2": "string",
    "additionalProp3": "string"
  }
}'

Uncaught PHP Exception ReflectionException: "Class "AnyType" does not exist" at MetadataFactory.php line 175

Generation Details

openapi-generator-cli \                        
    generate \
    -i openapi.yaml \
    -g php-symfony \
    -o .

Steps to reproduce

Related issues/PRs

its the same issue as this one was for typescript https://github.com/OpenAPITools/openapi-generator/issues/6332

Comienza ejecutando el comando proporcionado de openapi-generator con el generador php-symfony y el esquema de ejemplo usando additionalProperties. Sigue el tipo generado a través del procesamiento de la solicitud hasta llegar a vendor/jms/metadata/src/MetadataFactory.php. La tarea está terminada cuando el código generado de Symfony ya no hace referencia a un AnyType indefinido y el payload POST mostrado se puede procesar correctamente.