[Setting] Use @SystemApi to replace the hidden api

Bug: 145785535
Test: make
Change-Id: I32554eec8e9f0477a7342a8137a32939b5393fad

src/com/android/settings/ResetNetworkConfirm.java

@@ -105,9 +105,10 @@ public class ResetNetworkConfirm extends InstrumentedFragment {
             p2pFactoryReset(mContext);
 
             TelephonyManager telephonyManager = (TelephonyManager)
-                    mContext.getSystemService(Context.TELEPHONY_SERVICE);
+                    mContext.getSystemService(TelephonyManager.class)
+                            .createForSubscriptionId(mSubId);
             if (telephonyManager != null) {
-                telephonyManager.factoryReset(mSubId);
+                telephonyManager.resetSettings();
             }
 
             NetworkPolicyManager policyManager = (NetworkPolicyManager)