I would not. I used to even go in JUly without it but that was a couple decades ago. I've had too many sleepless nights. The issue in a city is that buildings are close together, you can't get any breeze and the streets are noisy anyway.
It is really just a guess, as it could be fine. I seem to recall a horrific heat wave end of June not that long ago. It was 2022 (not just France).
https://www.upi.com/Top_News/World-News/2022/06/17/france-Paris-heat-wave-france-spain-europe/2821655489911/
Paris reached 101 (38C) that june.
I don't rent apts much so don't have this problem. I have in the past and did have one of those portable things and it worked fine, but is good for only one room. It had to vent out a window through a hose.
IThose zinc roofs in Paris can heat up to almost 200F, by the way.