add: upload_folder_path element

Author: hahuyhoang411

docs/docs/features/multi-thread.md

@@ -22,12 +22,13 @@ For more information on threading, visit [Drogon's Documentation](https://github
 To increase the number of threads used by Nitro, use the following command syntax:
 
 ```bash title="Nitro deploy server format"
-nitro [thread_num] [host] [port]
+nitro [thread_num] [host] [port] [uploads_folder_path]
 ```
 
 - **thread_num:** Specifies the number of threads for the Nitro server.
 - **host:** The host address normally `127.0.0.1` (localhost) or `0.0.0.0` (all interfaces).
 - **port:** The port number where Nitro is to be deployed.
+- **uploads_folder_path:** To set a custom path for file uploads in Drogon. Otherwise, it uses the current folder as the default location. 
 
 To launch Nitro with 4 threads, enter this command in the terminal:
 ```bash title="Example"