Mirror compliance_total_unique_counts_monthly metric as Snowplow event

What does this MR do and why?

Related to #362280 (closed).

This mirrors the following Redis HLL events that are part of the redis_hll_counters.compliance.compliance_total_unique_counts_monthly metric as Snowplow events (a mirrored version of g_compliance_dashboard event has already been instrumented):

• i_compliance_credential_inventory
• i_compliance_audit_events
• g_compliance_audit_events
• a_compliance_audit_events_api

The Snowplow events are complete with a custom context for Redis metrics migrated to Snowplow events. See the new schema for details.

Screenshots or screen recordings

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How to set up and validate locally

1. Set up Snowplow Micro.
2. Satisfy one of the conditions in event descriptions at config/events/*.yml to fire a Snowplow event and observe it in Snowplow Micro at http://localhost:9091/micro/good or other configured URL.

MR acceptance checklist

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• I have evaluated the MR acceptance checklist for this MR.