Flexiglass: Disable hideKeyguardImpl when SceneContainer is enabled

When clicking on the Settings button on QS or notification shade while
lockscreen is on, the Intent doesn't launch successfully because
hideKeyguardImpl makes the lockscreen re-appear after collapsing
QS/notification shade. This call is not needed anymore when
SceneContainer is enabled, so we remove it to avoid the issue.

Bug: 398780316
Test: PlatformScenarioTests:android.platform.test.scenario.sysui.multiuser.OpenUserSettings
Flag: com.android.systemui.scene_container

Change-Id: Ifee63cb34e5d9afc85374f216e716fe4eb7ba65f