Change expand animation for private space container.

Only scroll to bottom. Don't use the animation.

bug: 299294792
test: manual:
video: https://drive.google.com/file/d/134Mq0MX0xauRfkNv8LGXOZgweRjqrmTa/view?usp=sharing
Flag: ACONFIG com.android.launcher3.Flags.private_space_animation TEAMFOOD
Change-Id: Ie6666638a53e334bddb1700674c2c49eb5788a06