deriveAsync with requiredSync is not lazy

[ShacharHarshuv]

When using deriveAsync with requireSync: true I still expect it to only run the computation once there is a usage (consumer) for the signal, which is how it works with angular built in computed, but it runs the computation immediately when derivedAsync is called.

A common usecase where this would be a problem is if the derivedAsync rely on the value of a required input signal.