use mall_price if historical_price of consumable is 0

[quarklikeadork]

because historical_price can be 0 #1125 instead of just being outdated, more changes might be needed elsewhere for this.

this was already using mall_price in older versions and the change to historical price was meant to avoid new searches when a mafia session is restarted, though normally the prices of food and drink have been bulk searched and after that historical prices should not be 0, but if they are, 0 would definitely be wrong

How Has This Been Tested?

run and cli

Checklist:

• My code follows the style guidelines of this project.
• I have performed a self-review of my own code.
• I have commented my code, particularly in hard-to-understand areas.
• I have based my pull request against the master branch or have a good reason not to.