Updates outdated status checks docs

What does this MR do and why?

What

Removes outdated status checks section in docs

Why

• Removes part that mentions that GitLab does not prevent merging as that has been implemented and is supported as Block merging if there are failed status checks (&8516 - closed) is completed and closed

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.

Related to &8516 (closed)