Improve history spec

Ignore order of returned keys

spec/chrono_model/time_machine/history_spec.rb

@@ -52,7 +52,7 @@
     describe 'does not add as_of_time when there are aggregates' do
       it { expect($t.foo.history.select('max(id)').to_sql).to_not match(/as_of_time/) }
 
-      it { expect($t.foo.history.except(:order).select('max(id) as foo, min(id) as bar').group('id').first.attributes.keys).to eq %w( id foo bar ) }
+      it { expect($t.foo.history.except(:order).select('max(id) as foo, min(id) as bar').group('id').first.attributes.keys).to match_array %w( id foo bar ) }
     end
 
     context '.sorted' do