message: fixed onFinish crash when worker reload.
diff: @@ -831,6 +831,10 @@ static int php_swoole_onFinish(swServer *serv, swEventData *req)
  if (swTask_type(req) & SW_TASK_CALLBACK)
  {
  callback = swHashMap_find_int(task_callbacks, req->info.fd);
  + if (callback == NULL)
  + {
  + swTask_type(req) = swTask_type(req) & (~SW_TASK_CALLBACK);
  + }
  }
  if (callback == NULL)
  {
  @@ -2583,7 +2587,9 @@ PHP_METHOD(swoole_server, task)
  #endif
  swTask_type(&buf) |= SW_TASK_CALLBACK;
  sw_zval_add_ref(&callback);
  - swHashMap_add_int(task_callbacks, buf.info.fd, sw_zval_dup(callback));
  +
  + zval *_callback = sw_zval_dup(callback);
  + swHashMap_add_int(task_callbacks, buf.info.fd, _callback);
  }
  swTask_type(&buf) |= SW_TASK_NONBLOCK;
  