ItemUtils: Update consumeItem to support dual-wielding

[prokopyl]

Right now the ItemUtils.consumeItem() helper method internally uses the getItemInHand Bukkit method, now deprecated because of dual-wielding.

Usages of getItemInHand should be removed, and the consumeItem() method should be changed to properly support dual-wielding, probably through an extra argument.

[AmauryCarrade]

For consistency with the Bukkit API, we could rename the existing method to consumeItemInMainHand (with a deprecated legacy fallback) and add another one consumeItemInOffHand.

[prokopyl]

Considering we are making all of the breaking changes in this version, do we want to not deprecate methods and just remove them directly?

Otherwise yes, I agree we should probably split the methods following Bukkit's naming convention.

[AmauryCarrade]

Yeah we could do this. We need a migration guide anyway.