Disable committing updates to TargetFrameworks file by default

Common/Scripts/UseTargetFrameworks.ps1

@@ -3,6 +3,14 @@ if ($args.Length -eq 0 -or ![bool]$args[0]) {
     exit(-1);
 }
 
+if ($args.Contains("--allow-git-changes")) {
+    Write-Warning "Changes to the default TargetFrameworks in Labs can now be committed. Run this command again without the --allow-git-changes flag to disable committing further changes.";
+    git update-index --no-assume-unchanged .\..\Labs.TargetFrameworks.props;
+}
+else {
+    git update-index --assume-unchanged .\..\Labs.TargetFrameworks.props;
+}
+
 $WasmTfm = "WasmLibTargetFramework";
 $UwpTfm = "UwpTargetFramework";
 $WinAppSdkTfm = "WinAppSdkTargetFramework";
@@ -63,7 +71,7 @@ if ($args.Contains("droid")) {
     $desiredTfmValues += $DroidTfm;
 }
 
-$targetFrameworksToRemove = $allTargetFrameworks.Where({-not $desiredTfmValues.Contains($_)})
+$targetFrameworksToRemove = $allTargetFrameworks.Where({ -not $desiredTfmValues.Contains($_) })
 
 $targetFrameworksToRemoveRegexPartial = $targetFrameworksToRemove -join "|";