docs: fix Korean language file extension mapping in README (kr to ko)

Author: ezAldinWaez

src/resources/language/README.md

@@ -19,7 +19,7 @@ This directory includes a set of built-in translations, including:
 | `_language-it.yml`    | Italian                      |
 | `_language-he.yml`    | Hebrew                       |
 | `_language-ja.yml`    | Japanese                     |
-| `_language-kr.yml`    | Korean                       |
+| `_language-ko.yml`    | Korean                       |
 | `_language-pl.yml`    | Polish                       |
 | `_language-pt.yml`    | Portuguese                   |
 | `_language-ru.yml`    | Russian                      |