Gatsby: code line highlighting buggy

[KyleAMathews]

https://twitter.com/rchrdnsh/status/1039529095372009472

[fk]

Sigh…

[fk]

Before actually looking closer at _anything_, I decided to throw the failing code block/highlighted lines in examples/using-remark…and it looks like this was working fine until [email protected]:

Using beta.7 (https://github.com/gatsbyjs/gatsby/pull/7342):

[DSchau]

@fk nice work debugging this! I can take a look at this tomorrow morning or maybe tomororw afternoon unless anyone else grabs it.

[fk]

@DSchau Oh I'd love that! Left another comment over at https://github.com/gatsbyjs/gatsby/pull/7342#issuecomment-420477709 a few minutes ago.

[fk]

Yay! 🎉 Let's unpin gatsby-remark-prismjs for www https://github.com/gatsbyjs/gatsby/blob/aa9bc1b353c2f83dad7d39d07f5a7c1b8ac092a0/www/package.json#L39