Fix appsec counterparts

Why is this change being made?

Pages using partial "handbook/engineering/metrics/partials/team_dashboard.erb", such as https://about.gitlab.com/handbook/engineering/development/sec/govern/#stable-counterparts, have incorrect data for Stable Counterparts.

This MR fixes the assignments based on https://about.gitlab.com/handbook/product/categories/.

It should also fix https://leipert-projects.gitlab.io/better-team-page/timezones/?search=threat%20insights.

Author Checklist

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• Added a description to this MR explaining the reasons for the proposed change, per say why, not just what
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