transparent-gateway-details.rst: Fix Radio-Co Processor firmware docker build

Adds sudo to docker commands, without them "permission denied" error message might show up.

Closes eclipse/oniro-core/docs#118 (closed)

Signed-off-by: Grzegorz Gwóźdź grzegorz.gwozdz@huawei.com

transparent-gateway-details.rst

@@ -22,8 +22,8 @@ The current manual process is quite intricated, but expect vast improvements in
 
 .. code-block:: bash
 
-   $ docker pull openthread/environment:latest
-   $ docker run -it --rm openthread/environment bash
+   $ sudo docker pull openthread/environment:latest
+   $ sudo docker run -it --rm openthread/environment bash
 
 - Inside the docker container prepare the build as follows: