🌐 [i18n-KO] Translated perf_train_special.md to Korean (#34590)

* Translated to Ko, 1st version

* updated _toctree.yml

docs/source/ko/_toctree.yml

@@ -206,8 +206,8 @@
       title: 다중 CPU에서 훈련하기
     - local: perf_train_tpu_tf
       title: TensorFlow로 TPU에서 훈련하기
-    - local: in_translation
-      title: (번역중) PyTorch training on Apple silicon
+    - local: perf_train_special
+      title: Apple 실리콘에서 PyTorch 학습
     - local: perf_hardware
       title: 훈련용 사용자 맞춤형 하드웨어
     - local: hpo_train