RFR(S): 7902624: Incorrect javadoc in jmh-core-it tests

[Dmitry Chuyko]

Hello,

Please review a mechanical cleanup in jmh-core integration tests' 
javadoc. Incorrect HTML with unescaped "->" is fixed by replacement with 
"→".

bug: https://bugs.openjdk.java.net/browse/CODETOOLS-7902624

webrev: http://cr.openjdk.java.net/~dchuyko/7902624/webrev.00/

The comment itself is not very informative, but at least it makes sense 
to make it correct.

-Dmitry