It all depends on how severe the crack is, it is only fine if crack is so minor that leaking isn't going to damage the engine right away.
Repair is an option too from local market, i heard about it but didn't check for it, you can if you want.
In my honest opinion if you're going to keep this car for quite some time then you should get it changed, you can't tell how bad this crack is and you wouldn't want your engine to seize.
Get it changed, take good care of Honda City because it's prone to get these cracks very often.