Move some global settings to secure settings

The following Settings are being moved to Settings.Secure
from Settings.Global since they are settings that exist
per user
- CHARGING_SOUNDS_ENABLED
- CHARGING_VIBRATION_ENABLED
- ZEN_DURATION
- SHOW_ZEN_UPGRADE_NOTIFICATION
- SHOW_ZEN_SETTINGS_SUGGESTION
- ZEN_SETTINGS_UPDATE
- ZEN_SETTINGS_SUGGESTION_VIEWED
zen_duration used to be a global setting -> move it to
Settings.Secure since users can set different values

Fixes: 110926544
Test: make RunSettingsLibRoboTests -j40 ROBOTEST_FILTER=ZenDurationDialogTest
Test: manual upgrade
Change-Id: Ifa36affe3e52e67a54698a8cf2c3424343877179