Add notice to Windows app page about unsupported ARM CPUs

[edwardivpn]

Consider adding a clear note to our Windows app page stating that ARM CPUs are currently unsupported.

https://www.ivpn.net/en/apps-windows/

We frequently receive complaints from users who are unable to install our app, only to later discover that their device uses an ARM chip. This note could help prevent confusion and reduce the need for troubleshooting explanations.