CE port of "Stablize editing scope label spec - retry if dropdown is not visible"

What does this MR do?

CE port of https://gitlab.com/gitlab-org/gitlab-ee/merge_requests/14841

Conformity

• [-] Changelog entry for user-facing changes, or community contribution. Check the link for other scenarios.
• [-] Documentation created/updated or follow-up review issue created
• Code review guidelines
• Merge request performance guidelines
• Style guides
• [-] Database guides
• Separation of EE specific content