Integrated: 8351081: Off-by-one error in ShenandoahCardCluster

[William Kemper]

Clean backport, simple change.

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Commit messages:
 - Backport 38b4d46c1ff3701d75ff8347e5edbb01acd9b512

Changes: https://git.openjdk.org/shenandoah-jdk21u/pull/176/files
  Webrev: https://webrevs.openjdk.org/?repo=shenandoah-jdk21u&pr=176&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8351081
  Stats: 1 line in 1 file changed: 0 ins; 0 del; 1 mod
  Patch: https://git.openjdk.org/shenandoah-jdk21u/pull/176.diff
  Fetch: git fetch https://git.openjdk.org/shenandoah-jdk21u.git pull/176/head:pull/176

PR: https://git.openjdk.org/shenandoah-jdk21u/pull/176