fix cargoQueue return type. Closes #1704

lib/cargoQueue.js

@@ -27,7 +27,7 @@ import queue from './internal/queue';
  * @param {number} [payload=Infinity] - An optional `integer` for determining
  * how many tasks should be processed per round; if omitted, the default is
  * unlimited.
- * @returns {module:ControlFlow.CargoObject} A cargoQueue object to manage the tasks. Callbacks can
+ * @returns {module:ControlFlow.QueueObject} A cargoQueue object to manage the tasks. Callbacks can
  * attached as certain properties to listen for specific events during the
  * lifecycle of the cargoQueue and inner queue.
  * @example