RFR: 8357109: Parallel: Fix typo in YoungedGeneration

[Guoxiong Li]

Hi all,

This trivial patch fixes two typos. Thanks for your review.

Best Regards,
-- Guoxiong

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Commit messages:
 - JDK-8357109

Changes: https://git.openjdk.org/jdk/pull/25436/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=25436&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8357109
  Stats: 2 lines in 1 file changed: 0 ins; 0 del; 2 mod
  Patch: https://git.openjdk.org/jdk/pull/25436.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/25436/head:pull/25436

PR: https://git.openjdk.org/jdk/pull/25436