Quiet MultiThreadedArrayCopyTest test case

[zli1]

This patch deletes test information that is displayed at standard output when the MultiThreadedArrayCopyTest test case succeeded

Fixes: #200

[ci skip]
Signed-off-by: Zhongyi.li1 zhongyi.li1@ibm.com

[smlambert]

Much better (output from grinder of quiet_MultiThreadedArrayCopyTest branch):

+++ j9vm.test.arraycopy.MultiThreadedArrayCopyTest: +++
command: /home/jenkins/workspace/Test-Grinder/openjdkbinary/j2sdk-image/jre/bin/java -Xcompressedrefs -Xgcpolicy:metronome -Xcompressedrefs -Xdump -Xms64m -Xmx64m -Xbootclasspath:/home/jenkins/workspace/Test-Grinder/openjdkbinary/j2sdk-image/jre/lib/amd64/compressedrefs/jclSC180/vm.jar:/home/jenkins/workspace/Test-Grinder/openjdkbinary/j2sdk-image/jre/lib/se-service.jar:/home/jenkins/workspace/Test-Grinder/openjdkbinary/j2sdk-image/jre/lib/rt.jar:/home/jenkins/workspace/Test-Grinder/openjdkbinary/j2sdk-image/jre/lib/resources.jar:/home/jenkins/workspace/Test-Grinder/openjdkbinary/j2sdk-image/jre/lib/jsse.jar:/home/jenkins/workspace/Test-Grinder/openjdkbinary/j2sdk-image/jre/lib/charsets.jar:/home/jenkins/workspace/Test-Grinder/openjdkbinary/j2sdk-image/jre/lib/jce.jar -classpath /home/jenkins/workspace/Test-Grinder/openjdk-tests/TestConfig/scripts/testKitGen/../../../../jvmtest/functional/VM_Test/VM_Test.jar:/home/jenkins/workspace/Test-Grinder/openjdk-tests/TestConfig/scripts/testKitGen/../../../../jvmtest/TestConfig/lib/asm-all.jar j9vm.test.arraycopy.MultiThreadedArrayCopyTest

--- Test PASSED ---

[smlambert]

thanks @zli1 !