(macos) jpackage tests timeout on MacPro5_1 systems

The following test timed out in the JDK16 CI:

tools/jpackage/share/IconTest.java

Typically when jpackage tests timeout we see some error in the
logs but that's not the case with this sighting. One thing I did
notice is that this test failure happened on a MacPro5_1 system.

The following test timed out in the JDK16 CI:

tools/jpackage/share/EmptyFolderPackageTest.java

The logs for this failure also do not show any errors for this
sighting. One thing I did notice is that this test failure happened
on a MacPro5_1 system.