Fixing dangling PS container on profile addition.

When Work profile state is changed, the all apps container is redrawn
Eventually `PrivateProfileManager.reset()` is also called but PS decorator
is not added as there is no change in PS state.
https://photos.app.goo.gl/V2bmZWfzBzcRP97C8
To fix this, we allow decorator addition on reset, but only
apply the same when its not already present in the recycler view.

Flag: ACONFIG com.android.launcher3.Flags.enable_private_space DEVELOPMENT
Bug: 313498792
Test: PrivateProfileManagerTest
Change-Id: I4c9a89d84e670ed45bf53a2d2e2c4922b165463e