Remove factories from IssuesMovedToIdForeignKey spec

spec/migrations/issues_moved_to_id_foreign_key_spec.rb

 require 'spec_helper'
 require Rails.root.join('db', 'migrate', '20171106151218_issues_moved_to_id_foreign_key.rb')
 
-# The schema version has to be far enough in advance to have the
-# only_mirror_protected_branches column in the projects table to create a
-# project via FactoryBot.
-describe IssuesMovedToIdForeignKey, :migration, schema: 20171114150259 do
-  let!(:issue_first) { create(:issue, moved_to_id: issue_second.id) } # rubocop:disable RSpec/FactoriesInMigrationSpecs
-  let!(:issue_second) { create(:issue, moved_to_id: issue_third.id) } # rubocop:disable RSpec/FactoriesInMigrationSpecs
-  let!(:issue_third) { create(:issue) } # rubocop:disable RSpec/FactoriesInMigrationSpecs
+describe IssuesMovedToIdForeignKey, :migration do
+  let(:issues) { table(:issues) }
+
+  let!(:issue_third) { issues.create! }
+  let!(:issue_second) { issues.create!(moved_to_id: issue_third.id) }
+  let!(:issue_first) { issues.create!(moved_to_id: issue_second.id) }
 
   subject { described_class.new }
 
   it 'removes the orphaned moved_to_id' do
     subject.down
 
-    issue_third.update(moved_to_id: 100000)
+    issue_third.update!(moved_to_id: 0)
 
     subject.up