Query parameter exploded object serialization

[LeweyM]

Hey,

The OpenAPI specs outline a way to serialize exploded object query parameters. This means that with a spec like the following:

query-parameters -> {shape: "square", color: "red"}

parameters:
  - in: query
    name: query-parameters
    schema:
      type: object
      properties:
          shape:
            type: string
          color:
            type: string
    style: form
    explode: true

You should be able to make requests like so: request?shape=square&color=red

With explode=true and style=form, the library should deserialise this to an object like {shape: "square", color: "red"}

This currently isn't supported by openapi-backend. Is this intentional?

If not, I'd be happy to make a PR.
Great library btw ❤️