Add feature toggle for policy scope

What does this MR do and why?

Add feature toggle for policy scope

To release the security policy scope as experiment we need a feature toggle. The feature will mostly be used for group level security policies.

Changelog: added EE: true

Screenshots or screen recordings

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NO VISUAL CHANGES

How to set up and validate locally

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

MR acceptance checklist

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

Related to #435501 (closed)