Replace Librarians' Novice-Tier Enchanted Book Trade with Candles

Right now Librarians' trades are easily abused. By breaking and replacing a lectern repeatedly, we can get any books we want. Gameplay would be more balanced if a Librarian's book trades are locked in before we know what they are.

Replacing the Novice-tier book trade with candles fixes this. It's also fairly consistent with their Apprentice-tier lantern trade.