I have this same exact problem with my game: https://jeffweber.itch.io/just-flip-demo
It really sucks and I have no idea to prevent this from happening.
Viewing post in Game file marked as virus when downloading
I think I solved it by myself! Until now I used 7zip to zip my files and thought that maybe this was the problem.
Without changing anything I zipped my file using WinZip and uploaded again. Just like magic the problem is now gone...no virus warning anymore!
Try the same thing and I am sure it will work. If you want download my game and please let me know if the download is completed without problem!
Link: https://savvu-games.itch.io/fruity-lips-endless-2d-runner