`file` shoud be an accepted primitive data type in swagger 2.0 spec

Describe the bug
See https://swagger.io/specification/v2/#specification, Section Data types.

An additional primitive data type "file" is used by the Parameter Object and the Response Object to set the parameter type or the response as being a file.

It seems this file data type exception is not accounted for Response object.

To Reproduce
Steps to reproduce the behavior:
openapi lint --format stylish spec.yml

Expected behavior
No spec error should be raised.

Logs

spec.yml:
  28:19  error    spec                    `type` can be one of the following only: "object", "array", "string", "number", "integer", "boolean", "null".
  3:1    warning  info-license            Info object should contain `license` field.
  20:5   warning  operation-operationId   Operation object should contain `operationId` field.
  24:7   warning  operation-4xx-response  Operation must have at least one `4xx` response.

OpenAPI definition

swagger: "2.0"

info:
  title: API
  version: 0.0.1
  description: |
    API

host: swagger.petstore
schemes:
  - https
basePath: /api/v1
consumes:
  - application/json
produces:
  - application/json; charset=utf-8

paths:
  /foo:
    get:
      summary: foo
      produces:
        - application/octet-stream
      responses:
        200:
          description: txt file
          schema:
            type: file

openapi-cli Version(s)
redocly/openapi-cli:v1.0.0-beta.80 container

Node.js Version(s)
See above.

Start by reproducing the reported error with the Swagger 2.0 specification shown in the issue and trace the openapi lint validation of the Response Object schema. Done means a response schema using type: file passes without the reported type error, while the existing warnings remain as appropriate.