Unable to build S3 example using provided instructions

The instructions say to use the provided Dockerfile to build the S3 example. However, it looks like something has changed as the build now fails:

```
# make
Scanning dependencies of target encoder
[ 50%] Building CXX object CMakeFiles/encoder.dir/main.cpp.o
[100%] Linking CXX executable encoder
/usr/include/c++/9.3.0/ext/string_conversions.h: In function '__to_xstring.constprop':
/usr/include/fortify/stdio.h:70:28: error: inlining failed in call to always_inline 'vsnprintf': function body can be overwritten at link time
70 | _FORTIFY_FN(vsnprintf) int vsnprintf(char *__s, size_t __n, const char *__f,
| ^
/usr/include/c++/9.3.0/ext/string_conversions.h:111:32: note: called from here
111 | const int __len = __convf(__s, __n, __fmt, __args);
| ^
lto-wrapper: fatal error: /usr/bin/c++ returned 1 exit status
compilation terminated.
/usr/lib/gcc/x86_64-alpine-linux-musl/9.3.0/../../../../x86_64-alpine-linux-musl/bin/ld: error: lto-wrapper failed
collect2: error: ld returned 1 exit status
make[2]: *** [CMakeFiles/encoder.dir/build.make:116: encoder] Error 1
make[1]: *** [CMakeFiles/Makefile2:97: CMakeFiles/encoder.dir/all] Error 2
make: *** [Makefile:104: all] Error 2
```

Please provide updated instructions for building the S3 example.

從提供的 Dockerfile 和 S3 範例的建置說明開始，然後使用 `make` 重現失敗，並檢查相關的 CMake 建置設定。更新說明以反映可正常運作的建置流程，並驗證依照文件中的步驟可以成功建置 S3 範例。

由索引模型根據 Issue 內容生成。