message: refactor MergeBox
diff: @@ -19,10 +19,8 @@ export default function MergeBox({ state }) {
  <Box ml={3} border={[true, 'green']}>
  <Caret edge='left'/>
  <Block py={2} px={4} border='bottom'>
  - <Text fontSize={2} fontWeight='bold'>This branch has no conflicts with the base branch</Text>
  - <Block pt={0}>
  - <Text fontSize={0}>Merging can be performed automatically</Text>
  - </Block>
  + <Text tag='p' m={1} fontSize={2} fontWeight='bold'>This branch has no conflicts with the base branch</Text>
  + <Text tag='p' m={1} mt={0} fontSize={0}>Merging can be performed automatically</Text>
  </Block>
  <Block py={2} px={4} bg='gray-light'>
  <Block py={1} pr={1} >
  