[Question] Generating JSON / YAML

[alexcastrodev]

Is your feature request related to a problem? Please describe.

In README file => Global Metadata, i think it has a missunderstanding (can be me, idk).
I noticed that we can generate json / yaml at the same time by using 2 objects in spec/swagger_helper.rb.

But based on PR 251, if you set the config.swagger_format, you will change all to json OR yaml.

Describe the solution you'd like

I created a PR, that says that you can use:
config.swagger_format = :yaml

But, to be honest, i want to know if is really possible to create json and yaml at the time.
if not, consider reviewing my contribution on Readme.md file

What support could we give you, so you could implement this yourself?

Yes, it's just a update on docs

Describe alternatives you've considered

Additional context

Relates to which version of OAS (OpenAPI Specification)