RFR: 8345970: pthread_getcpuclockid related crashes in shenandoah tests [v5]

[William Kemper]

> I haven't seen this failure mode in our Alpine Linux test pipelines, but the suggestion to avoid getting cpu time for terminated threads sounds sensible.

William Kemper has updated the pull request incrementally with one additional commit since the last revision:

  Turn test into assert

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Changes:
  - all: https://git.openjdk.org/jdk/pull/22693/files
  - new: https://git.openjdk.org/jdk/pull/22693/files/88bcf9ab..0e3d0a86

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=22693&range=04
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=22693&range=03-04

  Stats: 3 lines in 1 file changed: 0 ins; 1 del; 2 mod
  Patch: https://git.openjdk.org/jdk/pull/22693.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/22693/head:pull/22693

PR: https://git.openjdk.org/jdk/pull/22693