RFR: 8343481: Remove unnecessary @SuppressWarnings annotations (kulla) [v6]

[Archie Cobbs]

> Please review this patch which removes unnecessary `@SuppressWarnings` annotations.

Archie Cobbs has updated the pull request with a new target base due to a merge or a rebase. The incremental webrev excludes the unrelated changes brought in by the merge/rebase. The pull request contains nine additional commits since the last revision:

 - Revert changes to files imported from JLine to minimize diffs.
 - Merge branch 'master' into SuppressWarningsCleanup-kulla
 - Merge branch 'master' into SuppressWarningsCleanup-kulla
 - Merge branch 'master' into SuppressWarningsCleanup-kulla
 - Update copyright years.
 - Merge branch 'master' into SuppressWarningsCleanup-kulla
 - Remove two more "this-escape" supressions.
 - Merge branch 'master' into SuppressWarningsCleanup-kulla
 - Remove unnecessary @SuppressWarnings annotations.

-------------

Changes:
  - all: https://git.openjdk.org/jdk/pull/21855/files
  - new: https://git.openjdk.org/jdk/pull/21855/files/92d02591..94484883

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=21855&range=05
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=21855&range=04-05

  Stats: 85406 lines in 1316 files changed: 40828 ins; 38049 del; 6529 mod
  Patch: https://git.openjdk.org/jdk/pull/21855.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/21855/head:pull/21855

PR: https://git.openjdk.org/jdk/pull/21855