TimeScale doesnt effect to Observable.Timer(Scheduler.MainThread)

```
void Test()
{
Time.timeScale = 0;
Debug.Log(Time.time);

Observable.Timer(TimeSpan.FromSeconds(5), Scheduler.MainThread)
      Subscribe(_ =>
                    { 
                        Debug.Log(Time.time);
                    });

}
```
 Timer doesn't stop although TimeScale=0. And ofcourse two Time.time log return same result.