Fix unchecked runtime shutdown (#4575)

kotlin-native/backend.native/tests/interop/leakMemoryWithRunningThread/leakMemory.cpp

@@ -0,0 +1,15 @@
+#include "leakMemory.h"
+
+#include <atomic>
+#include <thread>
+
+extern "C" void test_RunInNewThread(void (*f)()) {
+    std::atomic<bool> haveRun(false);
+    std::thread t([f, &haveRun]() {
+        f();
+        haveRun = true;
+        while (true) {}
+    });
+    t.detach();
+    while (!haveRun) {}
+}