Retrofit如何避免multipart-form-data中的參數被雙引號夾起來

createApiService.kt

inline fun <reified T> createWebService(okHttpClient: OkHttpClient, url: String): T {
  val retrofit = Retrofit.Builder()
    .baseUrl(url)
    .client(okHttpClient)
    .addConverterFactory(ScalarsConverterFactory.create()) // <--- 避免產生雙引號在multipart-formdata的參數中
    .addConverterFactory(GsonConverterFactory.create()) // <-- ScalarsConverterFactory要放在GsonConverterFactory之前
    .addCallAdapterFactory(RxJava2CallAdapterFactory.create()).build()
  return retrofit.create(T::class.java)
}