Use \ instead of double spaces to add line breaks
https://github.com/apollographql/apollo-client-nextjs/pull/309/files#r1628079676
As noted in the other PR, GFM actually supports double spaces as line breaks (https://github.github.com/gfm/#hard-line-breaks), who knew!
This uses the other option of \
to indicate a line break so editors don't automatically clean it up and cause issues in the future