Add centralized compliance frameworks docs

What does this MR do and why?

This adds docs for centralised compliance framework management through the CSP group. The CSP group mechanism was added to docs here Add documentation for CSP (!195841 - merged)

References

Add documentation for CSP (!195841 - merged)

Centralized Compliance Management (GA) (&15864)

https://handbook.gitlab.com/handbook/engineering/architecture/design-documents/compliance_policy_instance_level_management/

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