Track types of secrets blocked and their cardinality

Overview

The aim is to track types of secrets detected and their cardinality when the feature is enabled in a GitLab instance.

Proposal

Use internal event tracking to count the number and type of secrets detected.

Considerations

• Coordinate with other track count issues:
  • Track count of suppressed secret detections (#443353 - closed) • Ethan Urie • 17.2
  • Track count of detected secrets (#443352 - closed) • Ethan Urie • 17.2
• Querying this data seems to be done via Snowplow if we do use the internal tracking events. Knowing how we would query this data could help inform what we include in the events we trigger and what events we trigger.
  • E.g., The easy way would be to create an event type per secret type and the event systems should manage the incrementing, but that would make querying all the secret types difficult (though probably the best route).

Implementation

Like in #443353 (closed), https://gitlab.com/gitlab-org/gitlab/blob/master/ee/lib/gitlab/checks/secrets_check.rb looks to be a good place to add the event creation.

Refinement Progress

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