[jdk17u-dev] RFR: 8371759: Add missing @Override annotations in com.sun.imageio package

[jyma22]

Hi all,

This pull request contains a backport of commit [0c6d1b9c](https://github.com/openjdk/jdk/commit/0c6d1b9c8bfd7f4e39a6621c7a8f7bdcd044a05f) from the [openjdk/jdk](https://git.openjdk.org/jdk) repository.

The commit being backported was authored by Sergey Bylokhov on 28 Nov 2025 and was reviewed by Tejesh R, Jayathirth D V and Alexander Zvegintsev.

Thanks!

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

Commit messages:
 - Backport 0c6d1b9c8bfd7f4e39a6621c7a8f7bdcd044a05f

Changes: https://git.openjdk.org/jdk17u-dev/pull/4211/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk17u-dev&pr=4211&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8371759
  Stats: 481 lines in 93 files changed: 401 ins; 0 del; 80 mod
  Patch: https://git.openjdk.org/jdk17u-dev/pull/4211.diff
  Fetch: git fetch https://git.openjdk.org/jdk17u-dev.git pull/4211/head:pull/4211

PR: https://git.openjdk.org/jdk17u-dev/pull/4211