Add skip lock screen in Notification & security lock screen settings

Users may have trouble finding this setting in face auth.
Heard this from dogfood/executive feedback and customer support discussion.
So add Skip Lock Screen preference in
Display > Lock screen display > What to show >
and
App & Notifications > Notifications > Lock Screen >

Bug: 138458558
Test: robotest & manual

Change-Id: I10e420821423821743d65b00c8b7e6d4d1224e00