[SettingsProvider] fix timestamp format in dump

Changing from:
1970-01-03 19:31:20 update screen_brightness

To:
2022-03-21 21:01:19 update screen_brightness

BUG: 225956913
Test: manual
Change-Id: I27d19779a207d8479b3ff4ed1e6343799d017d30

packages/SettingsProvider/src/com/android/providers/settings/SettingsState.java

@@ -618,7 +618,7 @@ final class SettingsState {
             return;
         }
         HistoricalOperation operation = new HistoricalOperation(
-                SystemClock.elapsedRealtime(), type,
+                System.currentTimeMillis(), type,
                 setting != null ? new Setting(setting) : null);
         if (mNextHistoricalOpIdx >= mHistoricalOperations.size()) {
             mHistoricalOperations.add(operation);