Newlines in MDX result in error

[gsklee]

In my MDX story if I write:

<Preview>
  <Story name="basicA">
    <Button>Label</Button>
  </Story>
  <Story name="basicB">
    <Button>Label</Button>
  </Story>
  <Story name="basicC">
    <Button>Label</Button>
  </Story>
</Preview>

then everything is good. But if I write

<Preview>
  <Story name="basicA">
    <Button>Label</Button>
  </Story>

  <Story name="basicB">
    <Button>Label</Button>
  </Story>

  <Story name="basicC">
    <Button>Label</Button>
  </Story>
</Preview>

then Storybook will give this error:

Module build failed (from ./node_modules/@mdx-js/loader/index.js):
SyntaxError: Unexpected token (4:10)
    at Object.raise (...)

I have a play around MDX's playground and this doesn't seem to happen there so I am assuming it's a Storybook issue.

[shilman]

closing as dupe to #7902