Remove 10 minute policy warning

What does this MR do and why?

Related issue #360293 (closed)

Now that !85744 (merged) is merged, scan policies are no longer subject to a delay of up to 10 minutes before they are applied, except in the edge case where the policies are pushed directly to the default branch of the security policy project. As a result, we can now update our documentation and remove the in-product UI warning on the Security & Compliance > Policies page.

Before

After

Screenshots or screen recordings

These are strongly recommended to assist reviewers and reduce the time to merge your change.

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.