What does this MR do and why?

• Default enable the FF.
• Change the FF type from gitlab_com_derisk to beta as we want to have the flexibility to rollback and have not got feedback yet from on-premise customers. gitlab_com_derisk does not support default enabling and beta type is ideal for this scenario.
• Include documentation for this feature enhancement.

Originally introduced in !143046 (merged)

MR acceptance checklist

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Related to #440652 (closed)