docs: remove deprecated docs in markdown-it

docs/packages/markdown-it.md

@@ -50,26 +50,3 @@ const md = MarkdownIt()
 
 md.use(fromHighlighter(highlighter, { /* options */ }))
 ```
-
-## Features
-
-### Line Highlight
-
-::: warning
-This is deprecated. It's disabled by default in `v0.10.0` and will be removed in the next minor. Consider use [`transformerNotationHighlight`](https://shiki.style/packages/transformers#transformernotationhighlight) instead.
-:::
-
-In addition to the features of `shiki`, this plugin also supports line highlighting. You can specify line numbers to highlight after the language name in the format `{<line-numbers>}` - a comma separated list of `<line-number>`s, wrapped in curly braces. Each line number can be a single number (e.g. `{2}` highlights line 2 and `{1,4}` highlights lines 1 and 4) or a range (e.g. `{5-7}` highlights lines 1 through 7, and `{1-3,5-6}` highlights lines 1 through 3 and 5 through 6). For example:
-
-````md
-```js {1,3-4}
-console.log('1') // highlighted
-console.log('2')
-console.log('3') // highlighted
-console.log('4') // highlighted
-```
-````
-
-::: info
-If line highlighting is not working, it may be due to compatibility issues with the [markdown-it-attrs](https://github.com/arve0/markdown-it-attrs) plugin. The syntax of `markdown-it-attrs` uses the same curly brace (`{}`) syntax that this plugin uses, which causes line highlighting to not work. If you wish to continue using `markdown-it-attrs` alongside this plugin, consider [changing the delimiter/syntax](https://github.com/arve0/markdown-it-attrs#custom-delimiters) of `markdown-it-attrs` to use a different character, such as `%`.
-:::