RFR(T): 8223427: [TESTBUG] Disable JTReg Shenandoah tests when Graal is enabled

[Pengfei Li (Arm Technology China)]

Hi,

Could anyone help review this patch (tiny change on 75 test files)?

Webrev: http://cr.openjdk.java.net/~pli/rfr/8223427/webrev.00/
JBS: https://bugs.openjdk.java.net/browse/JDK-8223427

JVMCI compiler supports only a few OpenJDK GCs (only Serial, Parallel, ParallelOld and G1). In current jtreg cases, when Graal is enabled, other GC test cases are skipped except Shenandoah.

We should add "!vm.graal.enabled" together with the "@requires vm.gc.Shenandoah" annotation in gc test cases to skip Shenandoah as well.

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Thanks,
Pengfei