🌐 [i18n-KO] Translated model_doc/barthez.md to Korean (#33980)

* docs: ko: model_doc/barthez.md

* feat: nmt draft

---------

Co-authored-by: Steven Liu <59462357+stevhliu@users.noreply.github.com>

docs/source/ko/_toctree.yml

@@ -322,8 +322,8 @@
         title: (번역중) ALBERT
       - local: model_doc/bart
         title: BART
-      - local: in_translation
-        title: (번역중) BARThez
+      - local: model_doc/barthez
+        title: BARThez
       - local: model_doc/bartpho
         title: BARTpho
       - local: in_translation