Fix HTTP Status Code load from OpenAPI 2.0 YAML

[hotuta]

I can't use HTTP Status Code integer load from OpenAPI 2.0 YAML.
But, I can use HTTP Status Code string load from OpenAPI 2.0 YAML.

Example

🆗

responses:
        '200':
          description: pet response
          schema:
            type: array
            items:
              $ref: "#/definitions/Pet"

🆖

responses:
        200:
          description: pet response
          schema:
            type: array
            items:
              $ref: "#/definitions/Pet"

OpenAPI 2.0 Document

https://swagger.io/docs/specification/2-0/describing-responses/

[brandur]

Oof yep, this seems like a good idea. Thanks!

[brandur]

Released as 2.0.1.