fix: remove invalid fields when generating oas 3 docs

[Eddayy]

Problem

Rswag::Specs::SwaggerFormatter supports default content type when you defined consumes or produces in swagger_doc but this only works for OAS 2 as it adds field that are incompatible with OAS 3

Solution

Remove invalid root fields when generating for OAS 3

This concerns this parts of the OpenAPI Specification:

I remove fields that do not belong in https://spec.openapis.org/oas/v3.1.0#fixed-fields

The changes I made are compatible with:

• OAS2
• OAS3
• OAS3.1

Related Issues

Links to any related issues.

Checklist

• Added tests
• Changelog updated
• Added documentation to README.md
• Added example of using the enhancement into test-app

Steps to Test or Reproduce

Add produces: or any key in the swagger_docs config, will remove any invalid fields if openapi is version 3

[joshraker]

For those looking for a workaround in the meantime, I've had success with adding an after(:spec) block to the swagger_helper config

RSpec.configure do |config|
  ...
  config.after(:suite) do
    spec.delete(:consumes)
    spec.delete(:produces)
  end
end

Edit: The suggestion above broke the OpenAPI spec generation. No requestBody blocks were generated.