Introduce Adding examples to the OAS3 Media Type Object (Request / Response)

[Dinushasilva]

This PR introduces to create an entire request or response examples by leveraging existing OAS3 capabilities by allowing multiple examples with arbitrary names.

Having multiple examples will increase user experience as it allows consumers to see different ways that an API can be consumed / requested.

This is by default supported in most documentation tooling to help users pick which example they'd like to see. We could also expand examples into Objects and Parameters at a later stage.

Before:

After:

Scalar:

Rapidoc

Stoplight

Swagger

I can update the docs, if we can agree on this implementation.

Thank you!

[shalvah]

Been busy, will take a look at these sometime this week or next.

[shalvah]

FYI, I've merged https://github.com/knuckleswtf/scribe/pull/792, which I think implements some of this functionality.