docs: Update api docs (#30)

Author: lan-yonghui

docs/dev_manual/api_manual.md

@@ -29,7 +29,7 @@ Token = md5('1panel' + API-Key + UnixTimestamp)
 
 ### 示例请求头：
 ```shell
-curl -X GET "http://localhost:4004/api/v1/resource" \
+curl -X GET "http://localhost:4004/api/v1/dashboard/current" \
 -H "1Panel-Token: <1panel_token>" \
 -H "1Panel-Timestamp: <current_unix_timestamp>"
 ```