How to reproduce:
1. Open the attached "1420601_Repro.zip" project
2. Double-click on "RoundedBorderArtifacts" Asset in the Assets folder to open UI Builder
3. Set the zoom level to 150% and inspect the corners of the square

Expected results: Corners are solid black color, no artifacts
Actual results: Red lines appear on the border corners coming out of the inner square's corners

Reproducible with: Built-in (2021.3.1f1, 2022.1.0f1, 2022.2.0a11)
Not reproducible with: 1.0.0-preview.18 (2019.4.38f1, 2020.3.33f1)

Notes:
- The artifacts are visible in the Game view
- There are couple of different artifacts:
Smooth line bleeding into the border from the inner square (visible on any zoom level)
A pixelated line appearing from the inner square corners (visible on zoom levels 50%, 150%, 250%)