message: refactor Heading defaultProps logic
diff: @@ -2,18 +2,13 @@ import React from 'react'
  import Text from './Text'
  const Heading = Text.withComponent('h1', true)
  -
  -Heading.defaultProps = {
  - fontSize: 5,
  - m: 0
  -}
  -
  -const {defaultProps} = Heading
  -Heading.h1 = Heading // .withComponent('h1') is redundant
  -Heading.h2 = Heading.withComponent('h2', {defaultProps})
  -Heading.h3 = Heading.withComponent('h3', {defaultProps})
  -Heading.h4 = Heading.withComponent('h4', {defaultProps})
  -Heading.h5 = Heading.withComponent('h5', {defaultProps})
  -Heading.h6 = Heading.withComponent('h6', {defaultProps})
  +Heading.defaultProps = {m: 0, fontSize: 5}
  +
  +Heading.h1 = Heading
  +Heading.h2 = Heading.withComponent('h2', true, {defaultProps: {m: 0, fontSize: 4}})
  +Heading.h3 = Heading.withComponent('h3', true, {defaultProps: {m: 0, fontSize: 3}})
  +Heading.h4 = Heading.withComponent('h4', true, {defaultProps: {m: 0, fontSize: 2}})
  +Heading.h5 = Heading.withComponent('h5', true, {defaultProps: {m: 0, fontSize: 1}})
  +Heading.h6 = Heading.withComponent('h6', true, {defaultProps: {m: 0, fontSize: 0}})
  export default Heading
  