RFR: 8378870: Remove sun.awt.AWTAccessor from imports in ImageIcon

[Alexey Ivanov]

A trivial change that removes `sun.awt.AWTAccessor` from imports in `ImageIcon`. This import is a left-over after `AppContext` was removed in https://github.com/openjdk/jdk/pull/29433 for [JDK-8376420](https://bugs.openjdk.org/browse/JDK-8376420).

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Commit messages:
 - 8378870: Remove sun.awt.AWTAccessor from imports in ImageIcon

Changes: https://git.openjdk.org/jdk/pull/29965/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=29965&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8378870
  Stats: 2 lines in 1 file changed: 0 ins; 2 del; 0 mod
  Patch: https://git.openjdk.org/jdk/pull/29965.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/29965/head:pull/29965

PR: https://git.openjdk.org/jdk/pull/29965