Update Docs/ProjectSpec.md
Update Docs/ProjectSpec.md

Co-Authored-By: Yonas Kolb <bbfdbc379b73fa413da737408efd028a0dda36c5@users.noreply.github.com>
yonaskolb/XcodeGen,yonaskolb/XcodeGen,yonaskolb/XcodeGen,yonaskolb/XcodeGen