RFR: 8350954: Fix repetitions of the word "the" in gc component comments

[Thomas Schatzl]

Hi all,

  please review this trivial change that fixes "the the" repetitions (and in this case grammar/wording) in the gc related sources.

If you think it's not worth fixing, I am okay with that and just retract the change.

Testing: gha

Thanks,
  Thomas

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Commit messages:
 - 8350954

Changes: https://git.openjdk.org/jdk/pull/23859/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=23859&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8350954
  Stats: 6 lines in 4 files changed: 0 ins; 0 del; 6 mod
  Patch: https://git.openjdk.org/jdk/pull/23859.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/23859/head:pull/23859

PR: https://git.openjdk.org/jdk/pull/23859