8320536: problemlist failing serviceability/attach/ConcAttachTest.java test on macosx

Reviewed-by: amenkov, dholmes

Author: plummercj

test/hotspot/jtreg/ProblemList.txt

@@ -134,7 +134,7 @@ serviceability/sa/ClhsdbPstack.java#core 8267433 macosx-x64
 serviceability/sa/TestJmapCore.java 8267433 macosx-x64
 serviceability/sa/TestJmapCoreMetaspace.java 8267433 macosx-x64
 
-serviceability/attach/ConcAttachTest.java 8290043 linux-all
+serviceability/attach/ConcAttachTest.java 8290043,8318866 linux-all,macosx-all
 
 serviceability/jvmti/stress/StackTrace/NotSuspended/GetStackTraceNotSuspendedStressTest.java 8315980 linux-all,windows-x64