Add new default skins' heads to creative inventory

The 'Player Head' has been an item in the creative inventory for a long time now, but it has only ever represented Steve's skin.

It has always been strange that Alex was missing but now there are even more default skins, so since the creative inventory is already going through a revamp (as of 1.19.3/1.20 snapshots), now would be the perfect time to allow Alex, Ari, Efe, Kai, Makena, Noor, Sunny, and Zuri's heads to join Steve's in the creative inventory!