Update screenshots of verification-windows-beginner.md
As mentioned in !1242 (merged): i couldn't update the screenshots in the verification-windows-beginner.html guide, since i don't have a windows environment yet. So i added a note warning about the outdated screenshots. I will open an issue about adding new screenshots.
I will work on it as soon as i have a Windows environment, but if somebody already one and can make the screenshots, please do.