RFR: 8361705: Clean up KlassCleaningTask

[Thomas Schatzl]

Hi all,

  please review this cleanup of `KlassCleaningTask`, fixing some style issues.

Testing: gha

Thanks,
  Thomas

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Commit messages:
 - 8361705

Changes: https://git.openjdk.org/jdk/pull/26289/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=26289&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8361705
  Stats: 11 lines in 2 files changed: 1 ins; 6 del; 4 mod
  Patch: https://git.openjdk.org/jdk/pull/26289.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/26289/head:pull/26289

PR: https://git.openjdk.org/jdk/pull/26289