Japanese translation of Rust by Example is broken

[dalance]

Location

Some paragraphs of https://doc.rust-lang.org/nightly/rust-by-example/ja/index.html is not translated.

Summary

This issue seems to be caused by an issue of mdbook-i18n-helpers which is integrated to src/tools/rustbook.
google/mdbook-i18n-helpers#202

So this will be fixed after fixing at the upstream and updating mdbook-i18n-helpers in src/tools/rustbook/Cargo.toml.

[dalance]

This issue will be fixed after merging #126566 and rust-lang/rust-by-example#1863.

[dalance]

The latest nightly was fixed.