javax/swing/JPopupMenu/7156657/bug7156657.java fails on macOS

This test was just stabilized under bug ID https://bugs.openjdk.java.net/browse/JDK-8171381

However a recent test run executing the jtregtests 40 times on JDK 17 for macOS 11 ARM reproduced it once - and that was using the fixed test.

So there's still a problem with this test although a rare-ish one.

Test log :
----------System.out:(0/0)----------
----------System.err:(13/782)----------
java.lang.RuntimeException: The test failed
at bug7156657.main(bug7156657.java:124)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:78)
at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.base/java.lang.reflect.Method.invoke(Method.java:568)
at com.sun.javatest.regtest.agent.MainWrapper$MainThread.run(MainWrapper.java:127)
at java.base/java.lang.Thread.run(Thread.java:831)

JavaTest Message: Test threw exception: java.lang.RuntimeException: The test failed
JavaTest Message: shutting down test

STATUS:Failed.`main' threw exception: java.lang.RuntimeException: The test failed
----------rerun:(42/7045)*----------