Improve PowerShell detection logic in baseline update script (#15522)

I did some more digging as this wasn't working on my Windows machine. I
figured out the specific PowerShell version that triggered the change,
and made the detection more accurate.

scripts/UpdateBaselines.ps1

@@ -1,7 +1,6 @@
-if (($PSVersionTable.Keys -contains "PSEdition") -and ($PSVersionTable.PSEdition -ne 'Desktop')) {
-    # PowerShell Core
+# https://learn.microsoft.com/en-us/powershell/module/microsoft.powershell.core/about/about_parsing#passing-arguments-that-contain-quote-characters
+if ($PSVersionTable.PSVersion -ge [System.Version]"7.3") {
     dotnet test --filter "TestCategory=Baseline" -- 'TestRunParameters.Parameter(name="SetBaseLine", value="true")'
 } else {
-    # PowerShell Desktop
     dotnet test --filter "TestCategory=Baseline" -- 'TestRunParameters.Parameter(name=\"SetBaseLine\", value=\"true\")'
 }