fix(cooldowns): Subtract time difference correctly

[axisiscool]

The current release of Knub subtracts cooldowns using:

Math.max(0, Date.now() - this.cooldownManager.get(key)!);

Doing it as it is now would always return 0, since the cooldown will always be greater than the current Date, hence flipping them would return the cooldown, and not 0 (unless there isn't a cooldown).

[Vetlix]

LGTM

[axisiscool]

Thank you @dexbiobot

[Dragory]

Good catch, thank you for the PR!