Update doc

Author: matoval

docs/source/developer_guide.rst

@@ -21,6 +21,7 @@ Unix Socket
 To send commands to unix socket without receptorctl by using socat to send data to the receptor socket directly.
 
 Example:
+
 .. code-block:: bash
 
    echo -e '{"command": "work", "subcommand": "submit", "node": "execution", "worktype": "cat", }\n"Hi"' | socat - UNIX-CONNECT:/tmp/control.sock