[Settings] Convert to getSystemService(Class<T>)

Change to getSystemService(Class<T>) to align the capability with framework
part.

Bug: 179640862
Test: local
Change-Id: I1b4812044fc4876bec6645570049a60f9470dbbd

src/com/android/settings/wifi/dpp/WifiDppUtils.java

@@ -403,8 +403,8 @@ public class WifiDppUtils {
      *                        device security or if lock screen is unlocked
      */
     public static void showLockScreen(Context context, Runnable successRunnable) {
-        final KeyguardManager keyguardManager = (KeyguardManager) context.getSystemService(
-                Context.KEYGUARD_SERVICE);
+        final KeyguardManager keyguardManager = context.getSystemService(
+                KeyguardManager.class);
 
         if (keyguardManager.isKeyguardSecure()) {
             final BiometricPrompt.AuthenticationCallback authenticationCallback =