message: add default border props to Box per
diff: import {withSystemProps, LAYOUT} from './system-props'
  -const Box = withSystemProps('div', LAYOUT)
  +const Box = withSystemProps(
  + {
  + is: 'div',
  + border: 0,
  + borderColor: 'gray.2'
  + },
  + LAYOUT
  +)
  export default Box
  