fix: Add SkiaSharp dependencies for Ubuntu CI

[afonsoft]

• Install required system libraries for SkiaSharp on Ubuntu
• Add libfontconfig1, libfreetype6, libx11-6, libxext6, libxrender1, libxtst6
• Fix DllNotFoundException for libSkiaSharp in CI environment
• Ensure tests can run properly with SkiaSharp graphics library

All Submissions:

• Have you followed the guidelines in our Contributing document?
• Have you checked to ensure there aren't other open Pull Requests for the same update/change?

New Feature Submissions:

1. Does your submission pass tests?
2. Have you lint your code locally prior to submission?

Changes to Core Features:

• Have you added an explanation of what your changes do and why you'd like us to include them?
• Have you written new tests for your core changes, as applicable?
• Have you successfully ran tests with your changes locally?

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

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