修复上一个版本出现的网络未连接，没有失败回掉的问题，单线程任务线程将不再失败重试，添加retry()，任务running状态下，5s钟保存一次状态

app/src/main/java/com/arialyy/simple/upload/FtpUploadActivity.java

@@ -34,8 +34,8 @@ import com.arialyy.simple.databinding.ActivityFtpUploadBinding;
  * Ftp 文件上传demo
  */
 public class FtpUploadActivity extends BaseActivity<ActivityFtpUploadBinding> {
-  private final String FILE_PATH = "/mnt/sdcard/Download/group_test_3/战斗吧剑灵.apk";
-  private final String URL = "ftp://172.18.104.66:21/upload/";
+  private final String FILE_PATH = "/mnt/sdcard/成都.mp3";
+  private final String URL = "ftp://172.18.104.229:21/upload/测试";
 
   @Override protected void init(Bundle savedInstanceState) {
     setTile("FTP 文件上传");