...

True, but those changes seem to have been significant, if you look at the change in filesize for the executable and others:

https://steamdb.info/patchnotes/17865742/

Of course that doesn't have to mean anything. Could still be a false positive or a local infection from another source or whatever.

Maybe OP could disclose the actual virus report, so we can see, what kind of threat it is supposed to be. Uploading the reported file(s) to virustotal.com could also help narrowing it down.