title: Download file with rn-fetch-blob with POST
body: <p>I'm use rn-fetch-blob, how can I download the file where I need to pass some parameters in the body of the request with POST? I've tried this:</p>
  
  <pre><code>RNFetchBlob
              .config({
                  // add this option that makes response data to be stored as a file,
                  // this is much more performant.
                  fileCache: true,
                  path: RNFetchBlob.fs.dirs.DownloadDir + '/video.mp4'
              })
              .fetch('POST', `${SERVER}/get_video`, {
                  unique_key: TerminalID(),
                  id_midia: '2'
              })
              .then((res) =&gt; {
                  // the temp file path
                  Alert.alert('Caminho', 'The file saved to ' + res.path())
                  this.setState({ download: true, downloadActionFinished: true })
              })
  </code></pre>
  
  <p>But the API don't receive the data that I pass on body of request </p>