Improve domain enrollment and desktop personalization

scripts/Initialize-SguDomainController.ps1

@@ -622,13 +622,7 @@ $collectorFqdn = "$env:COMPUTERNAME.$DomainName"
 $userPolicyParameters = @{
     TargetOuDn = $usersOuDn
     DomainController = $env:COMPUTERNAME
-}
-$wallpaper = Get-ChildItem -LiteralPath $PackageSharePath -File -ErrorAction SilentlyContinue |
-    Where-Object { $_.BaseName -eq 'wallpaper' -and $_.Extension -in @('.jpg','.jpeg','.png','.bmp') } |
-    Sort-Object Name |
-    Select-Object -First 1
-if ($wallpaper) {
-    $userPolicyParameters.WallpaperPath = "\\$env:COMPUTERNAME\Packages\$($wallpaper.Name)"
+    ClearManagedWallpaper = $true
 }
 & (Join-Path $scriptsRoot 'Set-SguDomainUserPolicies.ps1') @userPolicyParameters | Out-Null