fix: don't overwrite `propKeysManagedByAnimated` with `nil`

[kirillzyusko]

Summary

Do not overwrite propKeysManagedByAnimated with nil

Explanation

When you copy propKeysManagedByAnimated - you are copying nil. Later on in

[_mountingManager synchronouslyUpdateViewOnUIThread:tag changedProps:props componentDescriptor:*componentDescriptor];

props gets set to nil and then NSSet with transform key, but in

[componentView setPropKeysManagedByAnimated_DO_NOT_USE_THIS_IS_BROKEN:propKeysManagedByAnimated];

you set it back to nil.

As a result if re-render during animation happens, it may lead to unexpected jumps during the animation.

Test plan