[Java][retrofit2] Add the part name in the annotation for MultipartBody.Part.

Created by: cheparinV

Description

For MultipartBody.Part the part name is generated in the annotation.In Retrofit2 it is forbidden:

If the type is MultipartBody.Part the contents will be used directly. Omit the name from the annotation (i.e., @Part MultipartBody.Part part). javadoc

openapi-generator version

current maser (2d99836)

OpenAPI declaration file content or url

{
  "in": "formData",
  "type": "file",
  "name": "file
}

Expected: @retrofit2.http.Part MultipartBody.Part file Result: @retrofit2.http.Part("file") MultipartBody.Part file

Command line used for generation

Steps to reproduce

Related issues/PRs

Suggest a fix/enhancement

https://github.com/cheparinV/openapi-generator/tree/part-parameter