Remove redundant deps on `SharedNotificationContainerInteractor`.

Both `KeyguardInteractor` and `ShadeInteractorLegacyImpl` can get the
state they need from better-suited sources.

This is part of a refactoring that will improve NSSL positioning to
support Dual Shade and Connected Displays.

Bug: 338033836
Flag: com.android.systemui.scene_container
Test: Verified manually by observing that notifications placement is
 unaffected on lockscreen (both single shade and split shade modes),
 as well as during the transition from lockscreen to shade.
Test: Existing unit tests still pass.
Test: Updated unit tests.
Change-Id: I931c50f3fee68134fcfbdebfc44ac9e04c698be9