Add missing footnote to "Ruby 4.0.0 preview3 Released"

en, ja, ua

Author: Gao-Jun

en/news/_posts/2025-12-18-ruby-4-0-0-preview3-released.md

@@ -495,3 +495,4 @@ and is used all over the world especially for web development.
 [Feature #21550]: https://bugs.ruby-lang.org/issues/21550
 [Feature #21557]: https://bugs.ruby-lang.org/issues/21557
 [Bug #21654]:     https://bugs.ruby-lang.org/issues/21654
+[Feature #21552]: https://bugs.ruby-lang.org/issues/21552

ja/news/_posts/2025-12-18-ruby-4-0-0-preview3-released.md

@@ -425,3 +425,4 @@ Rubyはまつもとゆきひろ (Matz) によって1993年に開発が始めら
 [Feature #21550]: https://bugs.ruby-lang.org/issues/21550
 [Feature #21557]: https://bugs.ruby-lang.org/issues/21557
 [Bug #21654]:     https://bugs.ruby-lang.org/issues/21654
+[Feature #21552]: https://bugs.ruby-lang.org/issues/21552

ua/news/_posts/2025-12-18-ruby-4-0-0-preview3-released.md

@@ -493,3 +493,4 @@ Ruby уперше розробив Matz (Yukihiro Matsumoto) у 1993 році,
 [Feature #21550]: https://bugs.ruby-lang.org/issues/21550
 [Feature #21557]: https://bugs.ruby-lang.org/issues/21557
 [Bug #21654]:     https://bugs.ruby-lang.org/issues/21654
+[Feature #21552]: https://bugs.ruby-lang.org/issues/21552