Fixing 1.21.1 skull item issues

Updated internal libraries to work on versions up to 1.21.3

further pushing the compatibility

As promised, this free version should have been made compatible with upper versions.

Therefore fixed an error thrown by shops on upper versions

Changed plugin.yml name from RoyaleEconomy to RoyaleEconomyLegacy so it won't trigger API integrations in other plugins (which causes them to break since this version's API is old)

(Should not break eco plugin anymore)