It is a false positive.. Basically windows does that when the software isn't signed or has an invalid signing certificate, unverified, etc. I downloaded the new godot version (because it is what I am using to make PNGTuber-Remix) and the same thing happened today lol.
I cant get the software signed at the moment. So yeah, unfortunately this pop-up can happen. Just press more info and run. After that, it should be fine!