[Gameplay, Interface] Tahm Kench ult indicator bug

**Server:**EUW

**Type of Bug:**Interface

**Description:**When playing with a Tahm Kench on your team, his ulti ALWAYS looks like it's ready on the green button by his champion picture, even when it is used.

**Video / Screenshot:**None

**Steps to reproduce:**Play a game with a Tahm Kench on your team, Have him use his ulti. Observe how it looks like his ulti is still up, even though it is just spent, then weep when you hear that his bug has been there for over 18 months.

**Expected result:**The green ulti light by Tahms picture should go on cooldown

**Observed result:**The green ulti light by Tahms picture stays on. Forever.

**Reproduction rate:**100%

**System specs:**It don't matter, my friends have the same problem.