[Gameplay] Teleport+Unflinching Rune: Casting teleport on nothing gives the tenacity bonus

This is 100% reproducable

1. Take the "Unflinching" Rune in the resolve tree, and also take teleport
2. Use teleport on the ground and not on any unit
3. You will get a burst of tenacity according to the rune info panel, as well as the lingering tenacity. (Due to unflinching) TP does not go on cooldown because you never teleported to anything.
4. The effect disappears after a few seconds, but you can use teleport on nothing to get the burst of tenacity again.