[Feature] Add hint to report when using `nth-child(0)` in CSS

[antross]

🚀 Feature request

Description

The nth-child and related psedo-selectors are 1-based. Passing 0 silently fails in browsers today, leading to confusion and wasting developer time (see https://twitter.com/dan_abramov/status/1492277543185096704). By warning when these selectors are passed 0, webhint can help developers find and fix this issue faster.

Details

The set of 1-based selectors to look for:

• nth-child https://developer.mozilla.org/en-US/docs/Web/CSS/:nth-child
• nth-last-child https://developer.mozilla.org/en-US/docs/Web/CSS/:nth-last-child
• nth-of-type https://developer.mozilla.org/en-US/docs/Web/CSS/:nth-of-type
• nth-last-of-type https://developer.mozilla.org/en-US/docs/Web/CSS/:nth-last-of-type