Migrate chevron DM docs

What does this MR do and why?

A small MVC for Migrate angle icon to chevron in doc/user/proje... (#362780 - closed) where we migrate the angle icon to chevron in doc/user/project/issues/design_management.md.

Screenshots or screen recordings

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How to set up and validate locally

Numbered steps to set up and validate the change are strongly suggested.

MR acceptance checklist

This checklist encourages us to confirm any changes have been analyzed to reduce risks in quality, performance, reliability, security, and maintainability.

• I have evaluated the MR acceptance checklist for this MR.

Closes #362780 (closed)