Fix flaky test about ccache HOT 2 CLOSED

func Test_ConcurrentClearAndSet(t *testing.T) {
	for i := 0; i < 100000; i++ {
		var stop atomic.Bool
		var wg sync.WaitGroup

		cache := New(Configure[string]())
		r := func() {
			for !stop.Load() {
				cache.Set("a", "a", time.Minute)
			}
			wg.Done()
		}
		go r()
		wg.Add(1)
		cache.Clear()
		stop.Store(true)
		wg.Wait()
		cache.SyncUpdates()

		expectedCount := 0
		if cache.list.Head != nil {
			expectedCount = 1
		}
		assert.Equal(t, cache.ItemCount(), expectedCount)
	}
}

func Test_ClearSyncUpdates(t *testing.T) {
	for i := 0; i < 1000; i++ {
		cache := New(Configure[string]())
		go func() {
			cache.Set("a", "a", time.Minute)
			cache.Set("a", "a", time.Minute)
		}()
		cache.Clear()
		cache.SyncUpdates()

		expectedCount := 0
		if cache.list.Head != nil {
			expectedCount = 1
		}
		assert.Equal(t, cache.ItemCount(), expectedCount)
	}
}