resolveMdn no longer trustworthy?

還沒有人認領這個 Issue。

I have to replace many ` [ ](mdn: ) ` links and insert the full url in the spanish repo because they lead to 404

* some work ok,
* some give 404 and the lucky english link to click
* some give just the 404 and no other clue

it can not be solved by the engine
because some URL are translated too (some lang keep the same url, but Spanish and French translate some MDN url too)

I tested just one Arab article ( https://ar.javascript.info/prototype-inheritance ),
I got the same issue,

mdn: link obj.hasOwnProperty transforms to
https://developer.mozilla.org/ar/docs/Web/JavaScript/Reference/Global_Objects/Object/hasOwnProperty

404 with the lucky link this time.

首先從阿拉伯語文章中重現 `mdn: obj.hasOwnProperty` 連結，並將產生的 URL 與所描述的西班牙語和法語情況進行比較。檢查針對在地化 MDN 路徑的 `resolveMdn` 處理；當翻譯後的連結不再導向無法解釋的 404s，或被可靠的完整 URL 取代時，即表示完成。

由索引模型根據 Issue 內容生成。