Guard Get-ADTApplication against missing UpgradeCode registry key

In Windows Sandbox, and potentially other scenarios, `HKLM:\SOFTWARE\Microsoft\Windows\CurrentVersion\Installer\UpgradeCodes` doesn't exist until an MSI is installed

Author: pl4nty

src/PSAppDeployToolkit/Public/Get-ADTApplication.ps1

@@ -178,7 +178,7 @@ function Get-ADTApplication
 
         # Define compiled regex for use throughout main loop.
         $updatesAndHotFixesRegex = [System.Text.RegularExpressions.Regex]::new('((?i)kb\d+|(Cumulative|Security) Update|Hotfix)', [System.Text.RegularExpressions.RegexOptions]::IgnoreCase -bor [System.Text.RegularExpressions.RegexOptions]::Compiled)
-        $msiUpgradeCodeLookupTable = Get-ChildItem -Path HKLM:\SOFTWARE\Microsoft\Windows\CurrentVersion\Installer\UpgradeCodes\* | Get-ItemProperty | & {
+        $msiUpgradeCodeLookupTable = Get-ChildItem -Path HKLM:\SOFTWARE\Microsoft\Windows\CurrentVersion\Installer\UpgradeCodes\* -ErrorAction Ignore | Get-ItemProperty | & {
             begin
             {
                 # Open lookup table dictionary for returning at the end.