chore: replace Icon and Spinner with UI Kit variants

[Tuditi]

Summary

closes: #2376

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Testing

Platforms

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• Desktop
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Instructions

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Checklist

Please tick the following boxes that are relevant to your changes.

• I have followed the contribution guidelines for this project
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have added or modified tests that prove my changes work as intended
• I have verified that new and existing unit tests pass locally with my changes
• I have verified that my latest changes pass CI workflows for testing and linting
• I have made corresponding changes to the documentation