[jdk21u] RFR: 8317039: Enable specifying the JDK used to run jtreg

[Shivangi Gupta]

This contains the changes of this bug also.
https://bugs.openjdk.org/browse/JDK-8317807

Mach5 testing- https://mach5.us.oracle.com/mdash/jobs/sshivang-jdk21u-20231116-1225-2141342

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Commit messages:
 - Backport a250ae4d1b9c27757eb12d2f1673187c862149aa

Changes: https://git.openjdk.org/jdk21u/pull/374/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk21u&pr=374&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8317039
  Stats: 44 lines in 5 files changed: 42 ins; 0 del; 2 mod
  Patch: https://git.openjdk.org/jdk21u/pull/374.diff
  Fetch: git fetch https://git.openjdk.org/jdk21u.git pull/374/head:pull/374

PR: https://git.openjdk.org/jdk21u/pull/374