Remove ignored columns from geo_event_logs

What does this MR do and why?

This is the last step in cleaning up: Change the type of column geo_event_log.geo_eve... (#433432 - closed)

It removes two ignored columns in geo_event_logs table.

Related issue: #433432 (closed)

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ee/app/models/geo/event_log.rb

@@ -2,6 +2,8 @@
 
 module Geo
   class EventLog < ApplicationRecord
+    ignore_column :repositories_changed_event_id, remove_with: '17.4', remove_after: '2024-08-15'
+
     include Geo::Model
     include ::EachBatch