Merge branch 'remove_milestone_id_from_epics3' into 'master'

Remove milestone_id from epics table 3/3

See merge request gitlab-org/gitlab!23282

app/models/epic.rb

@@ -5,8 +5,6 @@
 class Epic < ApplicationRecord
   include IgnorableColumns
 
-  ignore_column :milestone_id, remove_after: '2020-02-01', remove_with: '12.8'
-
   def self.link_reference_pattern
     nil
   end

changelogs/unreleased/remove_milestone_id_from_epics3.yml

+---
+title: Remove milestone_id from epics
+merge_request: 23282
+author: Lee Tickett
+type: other