chore: Removes dependencies on React <19 in test utils

[pan-kot]

Description

The PR updates the uses of Simulate test-util from React with a custom event dispatcher.

Depends on: #3252

Rel: AWSUI-60345

How has this been tested?

• Existing unit tests pass with minor adjustments (calling change when the value remains the same now has no effect)
• Dry-run

Review checklist

The following items are to be evaluated by the author(s) and the reviewer(s).

Correctness

• Changes include appropriate documentation updates.
• Changes are backward-compatible if not indicated, see CONTRIBUTING.md.
• Changes do not include unsupported browser features, see CONTRIBUTING.md.
• Changes were manually tested for accessibility, see accessibility guidelines.

Security

• If the code handles URLs: all URLs are validated through the checkSafeUrl function.

Testing

• Changes are covered with new/existing unit tests?
• Changes are covered with new/existing integration tests?

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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 96.42%. Comparing base (20e6a83) to head (8b361da).

Additional details and impacted files

@@           Coverage Diff            @@
##             main    #3252    +/-   ##
========================================
  Coverage   96.42%   96.42%            
========================================
  Files         791      791            
  Lines       22603    22606     +3     
  Branches     7396     7745   +349     
========================================
+ Hits        21795    21798     +3     
+ Misses        801      754    -47     
- Partials        7       54    +47     

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[avinashbot]

I guess the same license thing from the test utils should apply here too? Will wait for that here as well (unless we don't need it here for some reason, and I don't have to).

[pan-kot]

I guess the same license thing from the test utils should apply here too? Will wait for that here as well (unless we don't need it here for some reason, and I don't have to).

No, I will remove the attributed code from this repo and import it from the test-utils instead.