Relocate one System.Core reference from last commit to the Tests project
Relocate one System.Core reference from last commit to the Tests project

Ooops, shouldn't have assumed that the tests project came after the main on

TechplexEngineer/Aurora-Sim,TechplexEngineer/Aurora-Sim,TechplexEngineer/Aurora-Sim,TechplexEngineer/Aurora-Sim