If the nick doesn't go all the way through the coating to the core, and it probably doesn't, I wouldn't worry about it. Your line won't soak up water and the nick won't weaken the line, it is just esthetic.

If the nick is within the first 6-12" of the line you could just cut the line without significantly affecting how it casts. Most lines have a 6" level tip section that some anglers remove anyway. Shortening the front taper much more than that will make turnover more forceful and delivery less delicate. For some anglers that is a good thing.
Bruce Richards