Guardrail generates invalid Scala method when operation has two parameters from different sources but with the same name

Hi, I have an existing server that for a certain path, receives a query parameter and a multi-part form parameter both with the same name (let's call it "foo"), plus other parameters. The relevant part in the swagger spec for that would be:

```yaml
/some/path:
post:
operationId: "theOperation"
produces:
- "application/json"
parameters:
- name: "foo"
in: "formData"
required: false
type: "string"
- name: "foo"
in: "query"
required: false
type: "string"
enum:
- "FIRST"
- "SECOND"
- "THIRD"
```

I believe that's valid swagger 2.0.

Guardrail generates the following definition for it:

```scala
def theOperation(respond: Resource.theOperationResponse.type)(foo: Option[String] = None, foo: Option[String] = None, ...): scala.concurrent.Future[Resource.theOperationResponse]
```

This fails to compile because Scala methods can't have two parameters with the same name.