Windows setup: update MinVersion

Starting from Go version 1.21, Windows 10 or Windows Server 2016 are
required

Signed-off-by: Nicola Murino <[email protected]>

windows-installer/sftpgo.iss

@@ -50,7 +50,7 @@ WizardStyle=modern
 ArchitecturesInstallIn64BitMode={#MyAppArch64}
 PrivilegesRequired=admin
 ArchitecturesAllowed={#MyAppArch}
-MinVersion=6.1sp1
+MinVersion=10.0.14393
 VersionInfoVersion={#MyVersionInfo}
 VersionInfoCopyright=AGPL-3.0
 SignTool=signtool