Add toggle for deleting task items

[tronfy]

When completing an ItemTask, the items in question get removed from the player's inventory. This PR adds a toggle to ExtraBingoMenu that controls whether that happens or not.

This is marked as a draft because:

• I have not decided on the styling and placement for this toggle.
• Updating from a previous version does not seem to work (deserialization fails), because data/presets.yml is not automatically updated, and I'm not sure how to fix that.

[Steaf23]

I think this feature would work better as a config option, not a game setting, as I don't see why you would want this to be different between games

[Steaf23]

And the way you would theoretically implement the serialization is check if the variable exists, and if doesnt, use a default value.

[tronfy]

I think this feature would work better as a config option, not a game setting, as I don't see why you would want this to be different between games

Fair point! Just reworked it as a config option.