disable gc/z/TestHighUsage.java

In order to reduce the noise in the JDK21 and JDK22 CIs, I'm disabling:

gc/z/TestHighUsage.java

This test (gc/z/TestHighUsage.java) has been ProblemListed by two different sub tasks:

JDK-8308844 ProblemList gc/z/TestHighUsage.java with Generational ZGC on windows x64

JDK-8311046 ProblemList gc/z/TestHighUsage.java with Generational ZGC

And neither of these ProblemListing work properly because this test is directly
invoking a Generational ZGC run:

    public static void main(String[] args) throws Exception {
        ProcessTools.executeTestJvm("-XX:+UseZGC",
                                    "-XX:+ZGenerational",
                                    "-XX:-ZProactive",
                                    "-Xms128M",
                                    "-Xmx128M",
                                    "-XX:ParallelGCThreads=1",
                                    "-XX:ConcGCThreads=1",
                                    "-Xlog:gc,gc+start",
                                    Test.class.getName())
                    .shouldNotContain("Allocation Stall")
                    .shouldHaveExitValue(0);
    }

The test also has:

 * @requires vm.gc.ZGenerational

so it won't run unless Generation ZGC is available for use as far as I can tell.

There are currently 7 sightings of this test failure linked in Mach5 and only 3 of those
sightings are in Generational ZGC tasks so this test is still free to execute in these
other tasks:

tier6-common-openjdk-open_test_hotspot_jtreg_hotspot_gc-windows-x64-open
tier7-rt-main-no-coops-open_test_hotspot_jtreg_hotspot_gc-windows-x64-debug
tier3-rt-LightweightLocking-tier1_gc-windows-x64-debug
tier3-rt-xShareOff-tier1_gc-macosx-x64-debug

So ProblemListing is NOT the right way to disable this test.