RFR: 8353129: CDS ArchiveRelocation tests fail after JDK-8325132

[Calvin Cheung]

Two archive relocation tests failed when `-XX:ArchiveRelocationMode=0` is specified via the jtreg `-javaoption`.
A fix is to add a `WhiteBox.getArchiveRelocationMode()` method so that the tests can check if the `ArchiveRelocationMode` is set to 0 before checking the expected output.

Passed tiers 1 - 4 testing.

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Commit messages:
 - whitespace error
 - 8353129: CDS ArchiveRelocation tests fail after JDK-8325132

Changes: https://git.openjdk.org/jdk/pull/24308/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=24308&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8353129
  Stats: 27 lines in 4 files changed: 21 ins; 1 del; 5 mod
  Patch: https://git.openjdk.org/jdk/pull/24308.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/24308/head:pull/24308

PR: https://git.openjdk.org/jdk/pull/24308