Added test to HeadlessChaos that tests adding and removing elements when there are attributes which have a dependency on their own group.
Updated the test in HeadlessChaos which tests circular dependencies now that they're allowed.
#preflight 646d35114422ba05f4bfad2a
#rb brice.criswell kriss.gossart
[CL 25591804 by Alex McAdams in ue5-main branch]