Update proofreader.md

doc/development/i18n/proofreader.md

@@ -57,6 +57,7 @@ are very appreciative of the work done by translators and proofreaders!
   - Chang-Ho Cha - [GitLab](https://gitlab.com/changho-cha), [Crowdin](https://crowdin.com/profile/zzazang)
   - Huang Tao - [GitLab](https://gitlab.com/htve), [Crowdin](https://crowdin.com/profile/htve)
   - Ji Hun Oh - [GitLab](https://gitlab.com/Baw-Appie), [Crowdin](https://crowdin.com/profile/BawAppie)
+  - Jeongwhan Choi - [GitLab](https://gitlab.com/jeongwhanchoi), [Crowdin](https://crowdin.com/profile/jeongwhanchoi)
 - Mongolian
   - Proofreaders needed.
 - Norwegian Bokmal