FIX: Update doc link details

Author: flame.yu

README.md

@@ -6,7 +6,9 @@ This project provides an Arduino compatible layer for the NXP I.MXRT series chip
 
 - RM EXPANSION MODULE
 
-For more information see Read the doc
+For more information, please use the online help document
+
+[Robomaster Expansion Module User Guide](https://rm-edu-boards.readthedocs.io/)
 
 # License and credits
 This project is licenced under the GNU General Public License v3.0 or later (GPL-3.0-or-later). A copy of the license is provided below and is also available at https://spdx.org/licenses/GPL-3.0-or-later.

README_CN.md

@@ -4,7 +4,9 @@
 
 - 机甲大师通用拓展模块
 
-更多资料详见 Read the doc
+获取更多资料，请参考在线帮助文档
+
+[RoboMaster扩展模块 用户指南](https://rm-edu-boards.readthedocs.io/)
 
 # License and credits
 本项目根据 GNU General Public License v3.0 or later (GPL-3.0-or-later) 进行授权 ，该许可证的副本可以从https://spdx.org/licenses/GPL-3.0-or-later中获取。

docs/source/arduino/arduino-1.md

@@ -23,8 +23,7 @@
 在 `附加开发板管理器网址`（*Additional Boards Managers URLs*）选项框中添加以下字段：
 
 ```
-！！！Realse版本需修改
-https://github.com/stm32duino/BoardManagerFiles/raw/main/package_stmicroelectronics_index.json
+https://raw.githubusercontent.com/RoboMaster/ArduinoCore-imxrt/index_file/package_robomaster_index.json
 ```
 
 2 回到ArduinoIDE中，单击`工具（tools）`,然后选择`开发板（Board）`>`开发板管理器（Boards Manager）`。