fix(flaws): don't report link to missing translation as broken if en-US fallback exists

[yin1999]

Summary

Resolves: https://github.com/orgs/mdn/discussions/144

stop report URL to not localized doc as broken

Problem

To reduce the workload on update the URLs which have pointed to en-US when a document is localized. We always make the URL pointed to a localized page, as Yari could fallback to en-US automatically. But it reports too many flaws (which may let the user change the link to point to en-US).

And in the above discuesstion, there is no maintainer has objected to stopping reporting such flaws.

Solution

Only modify the link if the linked page is not localized, and suggest to use localized URL (even if the page is not existed).

but we may need to reorganize the repair logic for links (with the flaws reporting).

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How did you test this change?

Modify the URL at the end of https://github.com/mdn/translated-content/blob/b96d6e1bd2f1b30ced085c2ca7088246a80b9ff4/files/zh-cn/web/html/element/input/search/index.md?plain=1#L133

如果没有指定 `incremental` ，则仅当用户显式启动搜索时（例如，在编辑字段时按 <kbd>Enter</kbd> 或 <kbd>Return</kbd> ）才发送 [`search`](/zh-CN/docs/Web/Events/search) 事件。

As the URL to search event is only in en-US and has a redirection.

Check if the suggestion is /zh-CN/docs/Web/API/HTMLInputElement/search_event.

And also check if there is any flaws about this link before we modify this URL (reporting this could fallback to en-US).

[awxiaoxian2020]

Any update for this PR?

[caugner]

Sincere apologies for the long wait @yin1999 and @awxiaoxian2020, and awesome work! 🙌