[ci]Fix running xaml styles in CI (#35426)

XAML style checkers aren't running right now in PR CI. This allowed some XAML style errors to cause build errors in release CI.

This PR contains the following fixes:
- Fix XAML style of files that have slipped.
- Add errors to the scripts that depend on dotnet commands if it fails.
- Add .NET 6 on CI so that applyXamlStyling.ps1 and verifyNugetPackages.ps1 run correctly again.

.pipelines/applyXamlStyling.ps1

@@ -117,7 +117,10 @@ else
         {
             Write-Error 'XAML Styling is incorrect, please run `.\.pipelines\applyXamlStyling.ps1 -Main` locally.'
         }
-
+        if ($lastExitCode -lt 0)
+        {
+            Write-Error "Error running dotnet tool run, with the exit code $lastExitCode. Please verify logs and running environment."
+        }
         # Return XAML Styler Status
         exit $lastExitCode
     }