Only call NotifEntry#getPromotedNotifContentModel when flag enabled.

NotificationEntry#getPromotedNotificationContentModel does a Log.wtf if the flag isn't enabled, but RenderNotificationListInteractor was accidentally calling #getPromotedNotificationContentModel even if the flag was disabled.

Bug: 369151941
Change-Id: Ie1ac8c963177ca5d6dc2601def3e88169274a312
Test: No WTF logs
Flag: android.app.ui_rich_ongoing
Flag: com.android.systemui.status_bar_notification_chips