RFR: 8353504: CDS archives are not found when JVM is in non-variant location [v2]

[Calvin Cheung]

> Although this fix reverts part of the change for [JDK-8348028](https://bugs.openjdk.org/browse/JDK-8348028), gtestLauncher still works the way it was described in JDK-8348028.
> Also added a test case to test the default CDS archive can be found from a non-variant location.
> 
> Sanity tested tiers 1 and 2.

Calvin Cheung has updated the pull request incrementally with one additional commit since the last revision:

  update test case comment

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Changes:
  - all: https://git.openjdk.org/jdk/pull/25361/files
  - new: https://git.openjdk.org/jdk/pull/25361/files/7ab3b809..78ff224b

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=25361&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=25361&range=00-01

  Stats: 1 line in 1 file changed: 1 ins; 0 del; 0 mod
  Patch: https://git.openjdk.org/jdk/pull/25361.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/25361/head:pull/25361

PR: https://git.openjdk.org/jdk/pull/25361