title: Why upload alamofire background request don't executes in background?
body: <p>I use alamofire in order to upload 30 mb zip file to server</p>
  
  <p>here is my request </p>
  
  <pre><code>let configuration = URLSessionConfiguration.background(withIdentifier: "identifire.com")
  
      alamoFireManager = Alamofire.SessionManager(configuration: configuration)
  
  let tempZipFilePath = UtilDirectory.tempZipPath.tweak()
  
      alamoFireManager.upload(URL(fileURLWithPath: tempZipFilePath),
                              to: deligate.url,
                              method: .post,
                              headers: headers)
          .uploadProgress(closure: {
              progress in
              print("Upload Progress: \(progress.fractionCompleted)")
          })
          .validate()
          .responseJSON {}
  </code></pre>
  
  <p>When request is starting I can see upload progress <code>uploadProgress(closure:_)</code> , but if I close the app uploading is paused. </p>
  
  <p>I expect that after closing the app request has to finish executing without interrupt. </p>
  
  <p>But why background upload request is stopping?</p>