The current version does not allow implementing the example. I am providing the answer from the official forum.

Sorry that it's an unsupported usage. because both at_test_cmd_test() and AT+HTTPCGET=params are executed in at_process_task(), however, in the current design, command processing is linear, and you cannot execute another command before one command is completed. in you case, you can create another task, and in your task, to execute some command like AT+HTTPCGET=. and at_test_cmd_test() to get the status of your task.