[jdk17u-dev] RFR: 8292407: Improve Weak CAS VarHandle/Unsafe tests resilience under spurious failures

[Vladimir Kempik]

Clean backport, helps weak and slow platforms to have stable test results

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Commit messages:
 - Backport 6e6202c14d0f6dd26369f21883ff317057aa469f

Changes: https://git.openjdk.org/jdk17u-dev/pull/1200/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk17u-dev&pr=1200&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8292407
  Stats: 951 lines in 45 files changed: 800 ins; 0 del; 151 mod
  Patch: https://git.openjdk.org/jdk17u-dev/pull/1200.diff
  Fetch: git fetch https://git.openjdk.org/jdk17u-dev pull/1200/head:pull/1200

PR: https://git.openjdk.org/jdk17u-dev/pull/1200