Minor editorial updates (infiniflow#700)

### What problem does this PR solve?

Editorial updates only. 

### Type of change

- [x] Documentation Update

README.md

@@ -114,12 +114,14 @@
 
 3. Build the pre-built Docker images and start up the server:
 
+   > Running the following commands automatically downloads the *dev* version RAGFlow Docker image. To download and run a specified Docker version, update `RAGFLOW_VERSION` in **docker/.env** to the intended version, for example `RAGFLOW_VERSION=v0.5.0`, before running the following commands.
+
    ```bash
    $ cd ragflow/docker
    $ chmod +x ./entrypoint.sh
    $ docker compose up -d
    ```
-   > Please note that running the above commands will automatically download the development version docker image of RAGFlow. If you want to download and run a specific version of docker image, please find the RAGFLOW_VERSION variable in the docker/.env file, change it to the corresponding version, for example, RAGFLOW_VERSION=v0.5.0, and run the above commands.
+
 
    > The core image is about 9 GB in size and may take a while to load.