新增章节：下载缓慢解决办法

src/SUMMARY.md

@@ -16,7 +16,7 @@
   - [墙推 VSCode!](first-try/editor.md)
   - [认识 Cargo](first-try/cargo.md)
   - [不仅仅是 Hello world](first-try/hello-world.md)
-  - [下载依赖很慢](first-try/slowly-downloading.md)
+  - [下载依赖太慢了？](first-try/slowly-downloading.md)
   - [避免从入门到放弃](first-try/sth-you-should-not-do.md)
   
 # Rust语言特性

内容变更记录.md

@@ -1,6 +1,11 @@
 # ChangeLog
 记录一些值得注意的变更。
 
+## 2022-04-7
+
+- 新增章节: [小试牛刀 - 下载太慢了?](https://course.rs/first-try/slowly-downloading.html)
+  
+  
 ## 2022-04-05
 
 - 新增章节：[Cookbook - 字符编码](https://cookbook.rs/encoding/strings.html)