Make Edit mode edge-to-edge

Instead of setting the padding from the inset in
NotificationsQuickSettingsContainer, we just set it directly in Compose.

Test: manual, single and split shade
Test: NotificationsQuickSettingsContainerTest
Fixes: 404584658
Flag: com.android.systemui.qs_ui_refactor_compose_fragment

Change-Id: I774bd47d1ad34cee7741f4ad78d7b19367767b28