[zh] Revise translation for notes shortcode

Currently, the three types of notes are translated as:

- `note` --> `注意：`
- `caution` --> `警告:`
- `warning` --> `警告：`

This PR revises the translation to:

- `note` --> `说明：`
- `caution` --> `注意：`
- `warning` --> `警告：`

i18n/zh.toml

@@ -2,7 +2,7 @@
 # 注意：修改此文件时请维持字符串名称的字母顺序并与英文版保持一致
 
 [caution]
-other = "警告:"
+other = "注意："
 
 [cleanup_heading]
 other = "清理现场"
@@ -164,7 +164,7 @@ other = "了解"
 other = "了解更多"
 
 [note]
-other = "注意："
+other = "说明："
 
 [objectives_heading]
 other = "教程目标"