Migrate epic events to snowplow vol. 2 - note & emoji events

What does this MR do and why?

Related to #366827 (closed)

Migrate some of the redis_hll_counters.epics_usage.epics_usage_total_unique_counts_monthly event's sub-events to Snowplow.

Screenshots or screen recordings

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How to set up and validate locally

1. Enable snowplow micro
2. Trigger any of the events migrated here: add/edit/destroy an epic's comment, add/remove an emoji reaction to an epic
3. Check if a new event with perform_epics_action action and se_property attribute describing the performed action has been registered at localhost:9090/micro/good

MR acceptance checklist

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