It shows that Iran has either not learnt how to protect the important AD radars with a layered overlapping AD setup, or lacks the technical capabilities to do so, both of which would be worrying for Iran right now.
This is most certainly Israel, trying to provoke Iran into a response, it is small enough to be discounted as the "provocation" event in itself, but the Iranian response could be used a pretext for war.
It is quite possible also, that drones are still being launched from Azerbaijan by Israel.