Replace unlit materials in create with new shape unlit property

[HifiExperiments]

after #1041, shapes now have their own unlit property, so we can remove the material entities from create that only served to make the gizmos unlit and just mark the shapes as unlit directly

that work was only done in the protocol_changes branch, so either we can remove them in that branch before it's merged to master, or just change it in master after protocol_changes is merged to master