RFR: 8346953: Remove unnecessary @SuppressWarnings annotations (client, #2)

[Archie Cobbs]

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

This issue is a follow up to [JDK-8343476](https://bugs.openjdk.org/browse/JDK-8343476) to remove some additional warnings that were missed in that issue.

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

Commit messages:
 - Remove unnecessary @SuppressWarnings annotations.

Changes: https://git.openjdk.org/jdk/pull/22906/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=22906&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8346953
  Stats: 27 lines in 9 files changed: 0 ins; 18 del; 9 mod
  Patch: https://git.openjdk.org/jdk/pull/22906.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/22906/head:pull/22906

PR: https://git.openjdk.org/jdk/pull/22906