Update design image and scaler to GitLab UI classes

What does this MR do?

This MR replaces outdated utility classes with GitLab UI utilities

Conformity

• Changelog entry
• Documentation (if required)
• Code review guidelines
• Merge request performance guidelines
• Style guides

Availability and Testing

• Review and add/update tests for this feature/bug. Consider all test levels. See the Test Planning Process.
• Tested in all supported browsers
• Informed Infrastructure department of a default or new setting change, if applicable per definition of done

Related issue: #219730 (closed)