StateScoped entity could cause "Could not despawn entity" warning

## Bevy version

v0.14.2

## What you did

I spawned an entity with `StateScoped(MyState)` component and a children with `StateScoped(MySubState)` component.

## What went wrong

If I exit `MyState`, both entities will first be despawned by `StateScoped(MyState)` (due to recursive despawn), and then the child entity will also be attempted to be despawned by `StateScoped(MySubState)`. It causes warning:

```
WARN bevy_ecs::world: error[B0003]: Could not despawn entity because it doesn't exist in this World. See: https://bevyengine.org/learn/errors/#
```

I think that the warning shouldn't be emitted in this case.