Bump markdown-it from 8.4.1 to 12.0.0

[dependabot-preview]

Bumps markdown-it from 8.4.1 to 12.0.0.

Changelog

Sourced from markdown-it's changelog.

[12.0.0] - 2020-10-14

Added

• .gitattributes, force unix eol under windows, for development.

Changed

• Added 3rd argument to highlight(code, lang, attrs), #626.
• Rewrite tables according to latest GFM spec, #697.
• Use rollup.js to browserify sources.
• Drop bower.json (bower reached EOL).
• Deps bump.
• Tune specsplit.js options.
• Drop Makefile in favour of npm scrips.

Fixed

• Fix mappings for table rows (amended fix made in 11.0.1), #705.
• %25 is no longer decoded in beautified urls, #720.

[11.0.1] - 2020-09-14

Fixed

• Fix blockquote lazy newlines, #696.
• Fix missed mappings for table rows, #705.

[11.0.0] - 2020-05-20

Changed

• Bumped linkify-it to 3.0.0, #661 + allow unlimited . inside links.
• Dev deps bump.
• Switch to nyc for coverage reports.
• Partially moved tasks from Makefile to npm scripts.
• Automate web update on npm publish.

Fixed

• Fix em- and en-dashes not being typographed when separated by 1 char, #624.
• Allow opening quote after another punctuation char in typographer, #641.
• Assorted wording & typo fixes.

[10.0.0] - 2019-09-11

Security

• Fix quadratic parse time for some combinations of pairs, #583. Algorithm is now similar to one in reference implementation.

Changed

• Minor internal structs change, to make pairs parse more effective (cost is linear now). If you use external "pairs" extensions, you need sync those with "official ones". Without update, old code will work, but can cause invalid result in rare case. This is the only reason of major version bump. With high probability you don't need to change your code, only update version dependency.
• Updated changelog format.
• Deps bump.

Commits

• 1731de4 12.0.0 released
• e70d5e5 Browser files rebuild
• 425e4a0 Drop makefile
• 4594d94 Simplify specsplit arguments
• 564de6b Deps bump & related updates
• f156ed1 Don't decode %25 in beautified urls
• 446bbcf Drop bower config
• a2cf20d browserify => rollup.js
• cb42dad changelog update
• 2aa9e03 Add .gitattributes, #719
• Additional commits viewable in compare view

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[dependabot-preview]

Superseded by #103.