!2819 修改website（不涉及翻译）

Merge pull request !2819 from Austin/OpenHarmony-3.1-Release

en/device-dev/website.md

@@ -34,6 +34,7 @@
     - [Burning Images](quick-start/quickstart-standard-burn.md)
     - [Running an Image](quick-start/quickstart-standard-running.md)
     - [FAQs](quick-start/quickstart-standard-faqs.md)
+- [Obtaining Source Code](get-code/sourcecode-acquire.md)
 - Compatibility and Security
   - [Privacy Protection](security/security-privacy-protection.md)
   - [Security Guidelines](security/security-guidelines-overall.md)

zh-cn/device-dev/website.md

@@ -57,6 +57,8 @@
       - [Hi3516开发板介绍](quick-start/quickstart-standard-appendix-hi3516.md)
       - [RK3568开发板介绍](quick-start/quickstart-standard-appendix-rk3568.md)
 
+- [获取源码](get-code/sourcecode-acquire.md)
+
 - 兼容性与安全
 
   - [隐私保护](security/security-privacy-protection.md)