[Bug] Enable hint-doctype by default

[antross]

This hint has been around since 2018 and is documented on webhint.io (https://webhint.io/docs/user-guide/hints/hint-doctype/). However it's not enabled by default in any of webhint's configurations (likely an oversight).

We should turn this on by default and perform any necessary cleanup in the process (e.g. switching to get locations from webhint's location-aware DOM that was added after the hint was initially authored).

[captainbrosset]

For information, fixing this also means that the webhint integration in Edge DevTools (in the Issues panel) will have the hint enabled. This means that when you navigate to a page that uses quirks mode (maybe by accident) and open DevTools, you'll get a warning for it. This is super useful when debugging weird layout issues! And will impact many many users.

[xxmathias]

Hello, I would like to get my hands on this issue.

Do you want to add a line before the doctype check in every .hmtl file in the whole project?

[ashutosh887]

@antross I would like to work on this