readOnly property not marked as optional in the generated model

Describe the bug
Fields marked as readOnly in a schema in the OpenAPI document are not set as optional in the generated model.
This makes them required in the body of any POST request in which this model is used, defeating the purpose of using the readOnly property.

OpenAPI Spec File

openapi: 3.1.0
info:
  title: Minimal bug reproduction API
  version: 1.0.0
paths:
  /bug:
    get:
      summary: Get all bugs
      responses:
        "200":
          description: A list of bugs
          content:
            application/json:
              schema:
                type: array
                items:
                  $ref: "#/components/schemas/Bug"
    post:
      summary: Create a bug
      requestBody:
        required: true
        content:
          application/json:
            schema:
              $ref: "#/components/schemas/Bug"
      responses:
        "201":
          description: Bug created
          content:
            application/json:
              schema:
                $ref: "#/components/schemas/Bug"

components:
  schemas:
    Bug:
      type: object
      properties:
        id:
          readOnly: true
          type: integer
        created_at:
          readOnly: true
          type: string
          format: date-time
        name:
          type: string
        description:
          type: string
        status:
          type: string
          enum:
            - open
            - closed
      required:
        - id
        - name
        - description
        - status
        - created_at

Desktop (please complete the following information):

• OS: [Windows 11]
• Python Version: [3.12]
• openapi-python-client version [0.22]

Comienza ejecutando la reproducción de OpenAPI 3.1 proporcionada con openapi-python-client 0.22 e inspeccionando el modelo Bug generado y el uso de POST. Rastrea dónde se convierten los campos readOnly y required; el trabajo estará terminado cuando los campos readOnly no sean obligatorios para la entrada de POST, pero sigan estando disponibles en los modelos de respuesta generados, con cobertura de regresión.