Default enable duo_secret_detection_false_positive

What does this MR do and why?

1. What: Set default enable of duo_secret_detection_false_positive to true
   1. Why: The flag has been enabled globally on prod
2. What: Fix missing link to the rollout_issue
   1. Why: There was a doc gap

References

• https://gitlab.com/groups/gitlab-org/-/work_items/17885
• #592047 (closed)

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How to set up and validate locally

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