fix: skip call executeBuiltInValidation if no sub-fields left

[newsiberian]

We've had a performance issue with useFieldArray and too many rows with validated fields. I've noticed that with function do some extra recursion with empty an fieldValue which mostly the reason of our issues

[bluebill1049]

thanks, could you plz add a test case for this as well? so it validates a correct ussecase.

[newsiberian]

Sure! I'm a bit busy atm. Will try to add tests during the next week

[newsiberian]

@bluebill1049 done. Please, check. Kinda looks strange, but I was unable to directly mock executeBuiltInValidation and that's the way that came into my mind.

[bluebill1049]

thanks for the improvement.