Function many_tasks_work

tests/system_test/stress_test.cpp:31–34

std::atomic<int> g_many_tasks_counter{0};

void many_tasks_work(void* /*arg*/) {
  g_many_tasks_counter++;
  sys_exit(0);
}

void test_many_tasks(void* /*arg*/) {
  klog::Info("=== Stress: Many Tasks Test ===");