Update README.md

lydia071 · lydia071 · commit a4f8c458f7e7 · 2024-01-24T14:58:30.000+08:00
diff --git a/README.md b/README.md
@@ -76,7 +76,7 @@ if (conn@connected) {
 dbClose(conn)
 ```
 
-## 3. Supported Data Types
+### 3. Supported Data Types
 
 R API supports the following data types of DolphinDB:
 
