feat: update readme

Author: weileifrank

HarmonyOS_NEXT/APIExample/README.md

@@ -32,7 +32,8 @@ To build and run the sample application, get an App Id:
     export const AppCertificate: String = YOUR APP CERTIFICATE
     ```
 
-6. Download the har package from the [official website](https://doc.shengwang.cn/doc/rtc/harmonyos/resources#%E4%B8%8B%E8%BD%BD-sdk) and copy it to `HarmonyOS_NEXT/APIExample/entry/libs/AgoraRtcSdk.har`
+6. Download the har package from the [official website](https://download.agora.io/sdk/release/Agora_Native_SDK_for_HarmonyOS_v4.4.1_FULL.har) and rename`AgoraRtcSdk.har`,then copy it to `HarmonyOS_NEXT/APIExample/entry/libs/AgoraRtcSdk.har`
+7. replace sign
 
 You are all set. Now connect your HarmonyOS NEXT device and run the project.
 

HarmonyOS_NEXT/APIExample/README.zh.md

@@ -31,7 +31,8 @@
     // 注意：App证书放在客户端不安全，推荐放在服务端以确保 App 证书不会泄露。
     export const AppCertificate: String = YOUR APP CERTIFICATE
     ```
-6. 在[官网](https://doc.shengwang.cn/doc/rtc/harmonyos/resources#%E4%B8%8B%E8%BD%BD-sdk)上下载har包，并复制到`HarmonyOS_NEXT/APIExample/entry/libs/AgoraRtcSdk.har`
+6. 在[官网](https://download.agora.io/sdk/release/Agora_Native_SDK_for_HarmonyOS_v4.4.1_FULL.har)上下载har包，重命名`AgoraRtcSdk.har`并复制到`HarmonyOS_NEXT/APIExample/entry/libs/AgoraRtcSdk.har`
+7. Replace the signature information in `build-profile.json5` under the root directory with your own.
 
 然后你就可以编译并运行项目了。