Xcode: Restore RunCMake.XcodeProject device tests in Xcode "new build system"
In !5229 (merged), I turned off a section of the RunCMake.XcodeProject
test that covers iOS cases because it does not work under the Xcode "new build system". I think the set of architectures may change, or something like that. To avoid blocking that MR, I'm opening this issue to track the remaining investigation needed for that test.