Reduce duplication in our process for program violations

Why is this change being made?

We had two disconnected sections, one for Rules of Engagement violations, and one for Code of Conduct violations. They should be treated in the same way after https://gitlab.com/gitlab-com/gl-security/security-department-meta/-/issues/1552+.

It was likely an oversight on my part to leave the Rules of Engagement section there. "Not giving credit" seems like an odd response for us to take, too.

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