RFR(T) 8230632: [TESTBUG] appcds/NonExistClasspath.java and ClassPathAttr.java failed when running in hotspot_appcds_dynamic test group

[Calvin Cheung]

bug: https://bugs.openjdk.java.net/browse/JDK-8230632

webrev: http://cr.openjdk.java.net/~ccheung/8230632/webrev.00/

Exclude the NonExistClasspath.java from the hotspot_appcds_dynamic test 
group.

Increase the timeout for the ClassPathAttr.java test.

Ran tests locally on linux-x64 and using mach5.

thanks,

Calvin