Integrated: 8350905: Shenandoah: Releasing a WeakHandle's referent may extend its lifetime

[William Kemper]

Clean backport.

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Commit messages:
 - Backport a347ecdedc098bd23598ba6acf28d77db01be066

Changes: https://git.openjdk.org/shenandoah-jdk21u/pull/178/files
  Webrev: https://webrevs.openjdk.org/?repo=shenandoah-jdk21u&pr=178&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8350905
  Stats: 10 lines in 1 file changed: 10 ins; 0 del; 0 mod
  Patch: https://git.openjdk.org/shenandoah-jdk21u/pull/178.diff
  Fetch: git fetch https://git.openjdk.org/shenandoah-jdk21u.git pull/178/head:pull/178

PR: https://git.openjdk.org/shenandoah-jdk21u/pull/178