RFR: JDK-8289798: Update to use jtreg 8

Fri Jul 11 09:10:19 UTC 2025

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.

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Commit messages:
 - 8361950: Set required version to 8+2
 - 8361950: Update to use jtreg 8

Changes: https://git.openjdk.org/jdk/pull/26261/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=26261&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8289798
  Stats: 11 lines in 9 files changed: 0 ins; 0 del; 11 mod
  Patch: https://git.openjdk.org/jdk/pull/26261.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/26261/head:pull/26261

PR: https://git.openjdk.org/jdk/pull/26261