Support multiple media types under the same status code

[iongion]

Checklist

• Run pytest tests and none is failing - They failed because they were already failing
• Run ruff check flask_openapi3 tests examples and no failed.
• Run mypy flask_openapi3 and no failed.
• Run mkdocs serve and no failed.

This PR is to be able to support multiple media types for the same status code of an endpoint

# Endpoints api = APIBlueprint( "default", __name__, doc_ui=True, ) class Project(BaseModel): Version: str Environment: str @api.get(  "/",  responses={  HTTPStatus.OK: {  "description": "Health check",  "content": {  # Content type  "application/json": Project,  "application/bson": Project,  },  },  }, ) def get_home(): """Check status.   Gets health status of the api.  """ output = Project(Version="1.0.0", Environment="dev") return output