Secret push protection OKR

What does this MR do and why?

De-links the secret push protection page based on feedback from Duo Chat.

I removed the entire Remove a secret from your commits and instead crosslinked to the tutorial, which covers the same material in greater depth.

Related items

https://gitlab.com/gitlab-org/technical-writing/team-tasks/-/issues/1404+

Review app

https://docs.gitlab.com/upstream-review-mr-ee-208375/user/application_security/secret_detection/secret_push_protection/