BBC just copied the consumerreports story. It has all the detail on how they did it. It's linked from the BBC article.
https://www.consumerreports.org/autonomous-driving/cr-engine...
https://www.consumerreports.org/autonomous-driving/cr-engine...
I mean, I guess this counts as "tricking" the car, but there's definitely a line somewhere at which point this becomes a Tesla-hating non-story. You could also put a brick on the accelerator in a normal car and crash yourself that way, but so what? Any safety system can be worked around by a sufficiently determined person.