First of all, stop relying that `InputManager` will successfully press
the gameplay test button, because it won't if it's obscured by the
notification overlay. Closing the overlay in a loop doesn't work because
there's a chance that a notification is posted, then all overlays are
closed, then another notification is posted, and so the button still
isn't clickable. Instead, use the `TestGameplay()` method directly.
Secondly, the notifications will still block `EditorPlayerLoader` from
transitioning to `EditorPlayer`. Here we have no other choice than to
aggressively dismiss notifications every spin of the relevant until
step and hope we eventually progress to `EditorPlayer`.
8171deec49