Add tracking epic for CM Scorecards

Why is this change being made?

While working on some housekeeping tasks for CI/CD, I noticed that today there's no easy way to see/find all complete Category Maturity Scorecards. We do track the UX Scorecards in this epic and cross-link that information in the handbook. However, for CM Scorecards there's no tracking epic and a considerable number of epics/issues are unlabelled, making it difficult for PDMs to assess the volume of CM Scorecards that groups/designers are working on.

This work is complementary to the JTBD evaluation, and it would be useful to cross-link these efforts within stages.

Since the CM Scorecard is more rigorous that the UX Scorecard process, I created a separate tracking epic for CM Scorecards. The epic is a collection point for all Category Maturity (CM) Scorecards that have been completed gitlab-org&6930

Author Checklist

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