fix(test): disable forced advanced auth in adminLoginAndValidate for WebView path

When useWebServerFlow=false, adminLoginAndValidate intends to start with
the in-app WebView so it can reach the Login Options and Login for Admins
menu items. But ensureRegularAuthServer was called without
forceAdvancedAuthentication=false, so the SDK re-launched a Custom Tab
over the WebView after the server re-selection. The Compose hierarchy was
then behind the tab, causing openLoginOptions() to crash with
"No compose hierarchies found in the app".

Pass forceAdvancedAuthentication=useWebServerFlow so that the WebView
path also clears the forced-advanced-auth flag, matching the in-app
WebView surface that topBarPage (a plain LoginPageObject) expects to drive.

Author: wmathurin

native/NativeSampleApps/AuthFlowTester/src/androidTest/java/com/salesforce/samples/authflowtester/testUtility/AuthFlowTest.kt

@@ -468,7 +468,7 @@ abstract class AuthFlowTest {
             else LoginPageObject(composeTestRule)
         val chromePage = ChromeCustomTabPageObject(composeTestRule)
 
-        ensureRegularAuthServer(expectCustomTab = useWebServerFlow)
+        ensureRegularAuthServer(expectCustomTab = useWebServerFlow, forceAdvancedAuthentication = useWebServerFlow)
 
         // Reach Login Options via the top bar (back-out is a no-op on the WebView path).
         topBarPage.backOutToLoginActivity()