refactor(filter-bar): migrate to svg icons

[spliffone]

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[gemini-code-assist]

Code Review

This pull request refactors the si-filter-pill component to use the new si-icon component for displaying the remove icon, replacing the old CSS-based approach. The changes are correct and well-implemented. The necessary imports and component updates in si-filter-pill.component.ts are done correctly, and the template in si-filter-pill.component.html is updated accordingly. The snapshot tests have also been updated to reflect the visual changes, which is good practice. Overall, this is a solid refactoring that improves consistency with the new icon system.

[github-actions]

[github-actions]

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