Missing "Cooldown" timer in Display

Hey there,

So I started recently playing this game a couple days ago and when I was deciding which Summoners Spell to use and I was stuck between Exhaust and a few other options. After reading all the options it was clear to me that Exhaust was the best one to pick because there is no cool-down like the other Spells. But in-game there is a 300 second cool-down which is not described like the other spells.

I obviously know now that there is a cool-down, but for other new players they might come across the same thing so I think it should be fixed/added. Thank you for your time