[Gameplay] Vayne Stutters Auto Attack after Tumbling Against Epic Monsters

As Vayne, when you Tumble and then attempt to auto attack any Epic Monster (e.g. Dragon), you'll stutter and not attack for about a second or two. It happens every time, and there doesn't seem to be a reason for it.

1. Load into game as Vayne.
2. Wait for Dragon to spawn.
3. Tumble and attempt to auto attack Dragon.

Mildly annoying bug.