[REQ] Openapi response examples

[emajo]

Is your feature request related to a problem? Please describe.

Working on the zapier generator came up the need to use response examples but actually are not supported by the generator.

Describe the solution you'd like

It would be great to have available in the templates the responses examples.

Describe alternatives you've considered

Additional context

There is already a TODO in the DefaultCodegen code -> https://github.com/OpenAPITools/openapi-generator/blob/fe78be405ed83c1d33045bc8bd5ea953f74a058f/modules/openapi-generator/src/main/java/org/openapitools/codegen/DefaultCodegen.java#L4778C5-L4780C59

I suppose there are multiple ways to define response examples, here I have a simple spec (example added with stoplight studio):

I'm referring to the examples inside responses.content.application/json.examples

openapi: 3.0.0
servers:
  - url: 'http://petstore.swagger.io/v2'
info:
  description: 'This is a sample server Petstore server. For this sample, you can use the api key `special-key` to test the authorization filters.'
  version: 1.0.0
  title: OpenAPI Petstore
  license:
    name: Apache-2.0
    url: 'https://www.apache.org/licenses/LICENSE-2.0.html'
tags:
  - name: pet
    description: Everything about your Pets
paths:
  /pet:
    post:
      tags:
        - pet
      summary: Add a new pet to the store
      description: ''
      operationId: addPet
      responses:
        '200':
          description: successful operation
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Pet'
              examples:
                example-1:
                  value:
                    id: 0
                    name: doggie
components:
  schemas:
    Pet:
      title: a Pet
      description: A pet for sale in the pet store
      type: object
      required:
        - name
        - photoUrls
      properties:
        id:
          type: integer
          format: int64
        name:
          type: string
          example: doggie