[ja] Broken table rendering on "GitHub language support"

### Code of Conduct

- [x] I have read and agree to the GitHub Docs project's [Code of Conduct](https://github.com/github/docs/blob/main/.github/CODE_OF_CONDUCT.md)

### What article on docs.github.com is affected?

https://docs.github.com/ja/get-started/learning-about-github/github-language-support

### What changes are you suggesting?

The language support table is displayed as raw Markdown text, including pipe characters and the separator row, instead of a table.

The equivalent English page renders correctly: https://docs.github.com/en/get-started/learning-about-github/github-language-support

Expected behavior: The Japanese page should render the language support matrix as a table.

### Additional information

_No response_

首先，比對 docs.github.com/ja/get-started/learning-about-github/github-language-support 的日文頁面與對應的英文頁面。檢查語言支援矩陣的在地化來源，以及其中的 Markdown 與正常運作的英文版本有何不同。當日文頁面將矩陣呈現為表格而不是原始 Markdown，且相關文件檢查通過時，即表示完成。

由索引模型根據 Issue 內容生成。