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

Attention: Patch coverage is 65.90909% with 15 lines in your changes missing coverage. Please review.

Project coverage is 96.38%. Comparing base (89612ae) to head (d311907).
Report is 2 commits behind head on main.

Files with missing lines	Patch %	Lines
src/test-utils/dom/input/base-input.ts	64.28%	5 Missing ⚠️
src/test-utils/dom/prompt-input/index.ts	66.66%	5 Missing ⚠️
src/test-utils/dom/textarea/index.ts	66.66%	5 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #3252      +/-   ##
==========================================
- Coverage   96.44%   96.38%   -0.07%     
==========================================
  Files         791      791              
  Lines       22563    22599      +36     
  Branches     7728     7399     -329     
==========================================
+ Hits        21760    21781      +21     
- Misses        750      811      +61     
+ Partials       53        7      -46     

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