Leona Sheild of Daybreak goes on cooldown without triggering

A while ago we dealt with the same thing on Nasus' Siphon Strike and Garens' Decisive Strike. It is the bug where upon auto attacking and the unit dying right before your auto attack hits. This results in no minion kill and the ability going on cooldown.

So far I have only seen it while having Relic Shield/Targon's Brace/Face of the Mountain.

Step 1: Play Leona

Step 2(Not sure if required): Buy one of the items listed above

Step 3: Attempt to kill a minion as it dies to something else