单元测试：testThreadPool() 中为啥不加 getchar() 就会报错呀？

1. test.cpp
<img width="960" alt="微信图片_20241125193755" src="https://github.com/user-attachments/assets/3e4982fe-ff41-4701-a07a-2956723b2e93">
2. threadpool.h
<img width="960" alt="微信图片_20241125194058" src="https://github.com/user-attachments/assets/ace8d13e-1a0a-4c98-bcbd-ff485a40a03b">

标题事项, 菜鸡求解，路过的大佬麻烦瞅一瞅~