Remove unused analytics events

[aduth]

🛠 Summary of changes

Removes an unused analytics event method.

Discovered using a little bash script combined with manual review:

for i in `rails runner 'puts AnalyticsEvents.instance_methods.join(" ")'`
do
  if ! grep -q -R 'app' --exclude app/services/analytics_events.rb -e $i
  then
    echo $i;
  fi
done

The removed method was added in #10392 and its last reference removed in #10861.

📜 Testing Plan

Verify there are no code references to the removed method.