RFR(xxs): 8196619: [TESTBUG] restore current version check in runtime/appcds/MultiReleaseJars.java

[Calvin Cheung]

JBS: https://bugs.openjdk.java.net/browse/JDK-8196619

webrev: http://cr.openjdk.java.net/~ccheung/8196619/webrev.00/

With javac supports --release 11, the temporary workaround for this test 
bug can be reverted.

Sanity tested with hs-tier1 and hs-tier2.

thanks,
Calvin