Add migration for a duplicate foreign key

db/migrate/20191107064946_update_oauth_open_id_requests_foreign_keys.rb

 # frozen_string_literal: true
 
-# rubocop: disable Migration/AddConcurrentForeignKey
-
 class UpdateOauthOpenIdRequestsForeignKeys < ActiveRecord::Migration[5.2]
   include Gitlab::Database::MigrationHelpers
 
   DOWNTIME = false
 
+  disable_ddl_transaction!
+
   def up
-    remove_foreign_key_if_exists(:oauth_openid_requests, column: :access_grant_id)
-    add_foreign_key(:oauth_openid_requests, :oauth_access_grants, column: :access_grant_id, on_delete: :cascade)
+    add_concurrent_foreign_key(:oauth_openid_requests, :oauth_access_grants, column: :access_grant_id, on_delete: :cascade, name: new_foreign_key_name)
+    remove_foreign_key_if_exists(:oauth_openid_requests, name: existing_foreign_key_name)
   end
 
   def down
-    remove_foreign_key_if_exists(:oauth_openid_requests, column: :access_grant_id)
-    add_foreign_key(:oauth_openid_requests, :oauth_access_grants, column: :access_grant_id, on_delete: false, name: 'fk_oauth_openid_requests_oauth_access_grants_access_grant_id')
+    add_concurrent_foreign_key(:oauth_openid_requests, :oauth_access_grants, column: :access_grant_id, on_delete: false, name: existing_foreign_key_name)
+    remove_foreign_key_if_exists(:oauth_openid_requests, name: new_foreign_key_name)
+  end
+
+  private
+
+  def new_foreign_key_name
+    concurrent_foreign_key_name(:oauth_openid_requests, :access_grant_id)
+  end
+
+  def existing_foreign_key_name
+    'fk_oauth_openid_requests_oauth_access_grants_access_grant_id'
   end
 end