bug: ajv example validation

Describe the bug

Steps to reproduce

    git clone https://github.com/mosoriob/loopback-next.git
   cd loopback-next/
   cd sandbox/validation-ajv
    npm install
    npm test

Current Behavior

The test fail with error:

Request POST /pets failed with status code 500. Error: strict mode: unknown keyword: "example"

Link to reproduction sandbox

https://github.com/mosoriob/loopback-next.git

More details

The API was generated using lb4 openapi

$ lb4 openapi pet.yaml
Loading pet.yaml...
? Select controllers and/or service proxies to be generated: OpenApiController
   create src/models/pet.model.ts
   create src/models/new-pet.model.ts
   create src/models/error.model.ts
   create src/controllers/open-api.controller.ts
npm WARN deprecated querystring@0.2.0: The querystring API is considered Legacy. new code should use the URLSearchParams API instead.

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found 0 vulnerabilities

Logs

No response

Additional information

Similar to: https://github.com/loopbackio/loopback-next/issues/4939

Reproduction

https://github.com/mosoriob/loopback-next.git

Comienza en la reproducción sandbox/validation-ajv y ejecuta npm install seguido de npm test para confirmar el error de strict-mode para la palabra clave example. Rastrea la API generada por lb4 openapi e identifica por qué la validación rechaza esa palabra clave; se considera terminado cuando la prueba de reproducción ya no falla con el error unknown-keyword.