Preserve DOCTYPE
Preserve DOCTYPE

Browsers render content differently whether it’s present or not.

Followed suggestion method https://github.com/GoogleChrome/puppeteer/issues/331

Signed-off-by: Frédéric Miserey <58692fd42329d32571d999fbcdd2ddd08a5186db@none.net>

stereobooster/react-snap,stereobooster/react-snap