Add documentation for warn more policy

What does this MR do and why?

Add documentation for warn more policy

• add it for the merge request widget

Changelog: changed

References

Screenshots or screen recordings

Before	After

How to set up and validate locally

MR acceptance checklist

Evaluate this MR against the MR acceptance checklist. It helps you analyze changes to reduce risks in quality, performance, reliability, security, and maintainability.

Related to #572453