A bankroll is an amount of money set aside for poker, which will not be needed for other purposes. Bankroll management mean playing in a way, that will reduce variance to an acceptable level for long term winning players. The basic idea being, that if you have no or very little money left due to a period of negative variance AKA bad luck, then you have to stop playing or move down significantly.
Which is an undesirable situation for long term winning players, since it reduce the amount of money, they can win. Therefore the original question is in fact about time management and not bankroll management. Working at McDonalds can also have a tremendous impact on your bankroll, if you set aside your salary for poker. But that does not make a question about working at McDonalds a bankroll management question