Fixed spell shop bug

[tukkek]

Hello, I have fixed a bug with the shop randomizer which was causing spell shops to consistently go from 90 Gil spells to 10,000 Gil spells. I haven't fully playtested it yet but I believe the fix is self-explanatory:

tukkek@c4000d4

You may also want to consider doing a full pull of the commits from my fork. Thank you!