Fixed the issue of crashes caused by the destruction of the EventPoll…

…er during process exit (#211)

src/Poller/EventPoller.cpp

@@ -79,7 +79,7 @@ void EventPoller::shutdown() {
 
     if (_loop_thread) {
         //防止作为子进程时崩溃
-        try { _loop_thread->join(); } catch (...) {}
+        try { _loop_thread->join(); } catch (...) { _loop_thread->detach(); }
         delete _loop_thread;
         _loop_thread = nullptr;
     }