The previous commits to shared.nsh resulted in auto-pinning only occurring in Windows 11 builds that weren't build number 22621 or higher, but a lot of users on Windows 11 are on 22621 already and the build number to pay attention to, when MS introduced the user confirmation for pinning popup, is in Windows 11, 22621, UBR 2361.
This commit checks for the UBR number too.

I modified the numbers locally and ran to confirm everything worked as expected.

I tested that the default flow doesn't trigger the system popup, and doesn't try to pin. And the custom flow doesn't show the option to pin in Setup.exe and doesn't try to pin.
I tested (by faking the numbers locally) that when the local UBR number is less than the 2361 number, the default flow does try to auto-pin and the custom flow gives the option to pin.