Fix styling of various dropdowns

What does this MR do?

This bumps @gitlab/ui to 24.3.1, which includes a fix for dropdown styles. See gitlab-ui!1878 (merged) for details.

Screenshots (strongly suggested)

See gitlab-ui!1878 (merged).

Does this MR meet the acceptance criteria?

Conformity

• Changelog entry
• [-] Documentation (if required)
• Code review guidelines
• [-] Merge request performance guidelines
• Style guides
• [-] Database guides
• Separation of EE specific content

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