[Sync EN] Add examples for mb_scrub() (#5811)

[github-actions]

Commit: https://github.com/php/doc-en/commit/eb10503592351cf78c25be21c60a9049784d57bb
PR: https://github.com/php/doc-en/pull/5811

Archivos ES a actualizar

• reference/mbstring/functions/mb-scrub.xml