[jdk20] RFR: 8295857: Clarify that cleanup code can be skipped when the JVM terminates (e.g. when calling halt())

[Brent Christian]

Backport [8295857](https://bugs.openjdk.org/browse/JDK-8295857) to jdk20

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Commit messages:
 - Backport c7aca73177339f931f7dfb6627365548a32874f7

Changes: https://git.openjdk.org/jdk20/pull/19/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk20&pr=19&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8295857
  Stats: 10 lines in 1 file changed: 5 ins; 0 del; 5 mod
  Patch: https://git.openjdk.org/jdk20/pull/19.diff
  Fetch: git fetch https://git.openjdk.org/jdk20 pull/19/head:pull/19

PR: https://git.openjdk.org/jdk20/pull/19