Add new API fo update secret push protection for group documentation

What does this MR do and why?

The code diff introduces a new API endpoint to manage group security settings, specifically the secret_push_protection_enabled setting. This feature helps protect against accidental secret pushing to a Git repository. Only group maintainers can access this endpoint and enable or disable the feature for all projects within the group. Additionally, maintainers can exclude specific projects from this protection. The code also includes necessary checks to ensure the feature is only available to users with the appropriate license and role.

Add a new API to update the group secret push protection.

EE: true Changelog: added

References

Add REST API endpoint to enqueue the background... (#502827 - closed) • Miki Amos • 17.7 • On track
Add documentation for group-level SPP REST API ... (#508502 - closed) • Gal Katz • 17.7

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