title: Fuel.upload with form data not sending form data
body: <p>Fuel Upload supports optional form data parameter.i passed this parameter and multipart data to upload , but only file upload works form data not associated with request</p>
  
  <p>val formData = listOf(
                  "title" to "test",
                  "desc" to "test")</p>
  
  <pre><code>    FuelRequest = Fuel.upload(URL, method = Method.POST, parameters = formData)
              .dataParts { request, url -&gt; listOf(DataPart(File(URL), "file")) }
  </code></pre>
  
  <p>i logged request object but it only contains.
  BTW if we pass empty data part array formdata will be submitted</p>
  
  <p>this is what request obj look like</p>
  
  <p>"Body : --163773469cc
  Content-Disposition: form-data; name="file"; filename="ydu.mp4"
  Content-Type:
  �������ftypmp42��������is</p>
  
  <p>and without file (empty datapart array)</p>
  
  <p>-"Body : --1637736aeab
  Content-Disposition: form-data; name="title"
  Content-Type: text/plain</p>
  
  <p>test</p>
  
  <p>--1637736aeab
  Content-Disposition: form-data; name="desc"
  Content-Type: text/plain</p>
  
  <p>test
  --1637736aeab--
  "
  "Headers : (3)"
  Accept-Encoding : compress;q=0.5, gzip;q=1.0
  Content-Type : multipart/form-data; boundary=1637736aeab</p>