Fix CanAttack for mirages following rP25465

CanAttack queries the miraged Resistance which did not exist, thus failing.
This mirages Resistance explicitly (fixing parts of #5883)

Fixes rP25465, reverts the mirage.xml change in rP25368

Refs #5883

Reported by: Asger_Spear

Differential Revision: https://code.wildfiregames.com/D4001