Enable secondary_user_on_secondary_display for CtsScopedStorageRedactUriTest

secondary_user_on_secondary_display is for background users that have
access to UI on assigned displays (a.k.a. visible background users) on devices
that have config_multiuserVisibleBackgroundUsers enabled. The main use
case is Automotive's multi-display Whole Cabin experience where
passengers (modeled as visible background users) can interact with the display
in front of them concurrently with the driver (modeled as the the
current user) interacting with driver's display.

Fixes include
- Enabling the config

Change-Id: I4bb7fb5f602ff68b7cb58459f49dc0060e057db6
Flag: NONE (bugfix)
Bug: 364643614
Test: atest CtsScopedStorageRedactUriTest
Test: atest --user-type secondary_user_on_secondary_display CtsScopedStorageRedactUriTest