RFR: 8361950: Update to use jtreg 8 [v6]

[Jaikiran Pai]

On Thu, 18 Sep 2025 05:52:07 GMT, Christian Stein <cstein at openjdk.org> wrote:

>> Please review the change to update to using jtreg 8.
>> 
>> 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.
>
> Christian Stein has updated the pull request incrementally with one additional commit since the last revision:
> 
>   Fix copyright header
>   
>   [skip ci]

The latest changes in `fd7bf6f` look good to me.

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Marked as reviewed by jpai (Reviewer).

PR Review: https://git.openjdk.org/jdk/pull/26261#pullrequestreview-3237379113