RollDone() doesnt run after rolling the dices for a second time

[p-freitas]

Hi Adam!

I'm having an issue where, after I decrease the numDice number and roll the dices a second time, it doesnt run the RollDone() callback. You can test it in the demo.

Steps:
-Choose a dice number and roll it
-Decrease the dice number and roll it again

You will see that the rollDone() callback wont be called