docs(readme): update formatting

Author: hsiang-han

README.md

@@ -60,10 +60,10 @@ Migrated to `hexgrad/Kokoro-82M-v1.1-zh` with baseline adaptation based on the c
 1. 准备环境
    - 安装并启动 [Docker Desktop](https://www.docker.com/products/docker-desktop/)
    - 打开终端，确认 Docker 可用：
-  ```bash
-  docker --version
-  docker compose version
-  ```
+    ```bash
+    docker --version
+    docker compose version
+    ```
 
 2. 拉取代码（使用本仓库）