FormField's value not updated when TextEditingController not supplied

[alyyasser]

there's strange issue when creating PinInputTextFormField without supplying TextEditingController in constructor parameter. when using TextEditingController from inside _PinInputTextFormFieldState, it'll not update the value, that value will be used in validator, onSave, and other callback in PinInputTextFormField.

after investigating the logic i implemented before, it turns out i did it wrong (sorry). will land the PR to fix it soon. i've done the fix in my local repo.

[TinoGuo]

Thanks for your contribution. Don't feel guilty, you're pretty good.