[15] RFR(T) 8247527: serviceability/dcmd/gc/HeapDumpCompressedTest.java fails with Graal + ZGC

[Vladimir Kozlov]

https://cr.openjdk.java.net/~kvn/8247527/webrev.00/
https://bugs.openjdk.java.net/browse/JDK-8247527

Test should have @requires which excludes running Graal with GC which it does 
not support.

Testing: hs-tier1,hs-tier4-graal

Thanks,
Vladimir