Clear expected child failure codes after regression assertions

tests/Test-ConfigurationReadOnlyWindows.ps1

@@ -13,4 +13,7 @@ catch { $caught = $_.ToString() }
 if ($caught -notmatch 'exit: 9' -or $caught -notmatch 'WELA-smoke-diagnostic') {
     throw "Native exit/stderr capture failed: $caught"
 }
+# The intentionally failed child was asserted above; do not leak its expected
+# exit code into a CI shell wrapper after a successful smoke test.
+$global:LASTEXITCODE = 0
 Write-Host "Read-only Windows smoke checks passed (process creation audit mask: $mask). No Windows settings changed."

tests/Test-ConfigurationResults.ps1

@@ -166,6 +166,9 @@ try {
     $encoded = [Convert]::ToBase64String([Text.Encoding]::Unicode.GetBytes($child))
     $childOutput = @(& $engine -NoProfile -EncodedCommand $encoded 2>&1)
     $childExit = $global:LASTEXITCODE
+    # GitHub's PowerShell wrapper propagates LASTEXITCODE after the script. This
+    # child was deliberately failed; assertions below decide the test outcome.
+    $global:LASTEXITCODE = 0
     Assert ($childExit -eq 1) 'The actual configure dispatcher returns nonzero for a failed control report'
 
     # CA-specific wrapper: registry read succeeds, certutil succeeds, restart