Avoid using derivedStateOf for QS Y translation

derivedStateOf is expensive and isn't really a good fit for the Y translation as it changes just as often as the QS expansion state

Flag: com.android.systemui.qs_ui_refactor_compose_fragment
Bug: 418728219
Test: manually - expanding QS from lockscreen
Change-Id: Idc282559768312d92962c5a0be90f5d09d4335b4