[Dual Shade] Fix ShadeStartableTest for Dual Shade on.

This ensures these unit tests do not fail when Dual Shade is the default
shade experience in scene container.

Bug: 376411622
Test: Updated unit tests.
Flag: com.android.systemui.scene_container
Change-Id: Ie51ac87ff107a2e3d561fc6b70774ad4d7ddb8ca