Review request JDK-8068242: quarantine the test IsModifiableClassAgent.java until JDK-8068162 is resolved

[Alexander Kulyakhtin]

Hi,

Could I, please, have a review of this fix. This is a oneline change to quarantine a test until JDK-8068162 is resolved

bug: https://bugs.openjdk.java.net/browse/JDK-8068242
webrev: http://cr.openjdk.java.net/~eistepan/~akulyakhtin/8068242/webrev.00/

@ignore JDK-8068162 added to the test to have it ignored until JDK-8068162 is resolved

Thanks,
Alexander