RFR: JDK-8266254: Update to use jtreg 6 [v2]

[Jonathan Gibbons]

> Please review the change to update to using jtreg 6. 
> 
> The primary change is to the jib-profiles.js file, which specifies the version of jtreg to use, for those systems that rely on this file. In addition, the `requiredVersion` has been updated in the various `TEST.ROOT` files.
> 
> All the tests that could be updated ahead of time have been updated. There are a few tests remaining that need to be done at this time, because of the change in the module name for TestNG 7.3. It changed from a default of `testng` to and explicit `org.testng`.

Jonathan Gibbons has updated the pull request incrementally with one additional commit since the last revision:

  Update copyright years

-------------

Changes:
  - all: https://git.openjdk.java.net/jdk/pull/4315/files
  - new: https://git.openjdk.java.net/jdk/pull/4315/files/0d1e554a..4ef5614f

Webrevs:
 - full: https://webrevs.openjdk.java.net/?repo=jdk&pr=4315&range=01
 - incr: https://webrevs.openjdk.java.net/?repo=jdk&pr=4315&range=00-01

  Stats: 6 lines in 6 files changed: 0 ins; 0 del; 6 mod
  Patch: https://git.openjdk.java.net/jdk/pull/4315.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/4315/head:pull/4315

PR: https://git.openjdk.java.net/jdk/pull/4315