Add should use default unfold transition attribute to wallpaper

Adds new attribute to wallpaper XML declaration to indicate
whether a wallpaper should receive default zooming transition
updates when folding or unfolding. This attribute allows to
opt-out from the default behaviour during this transition and
implement custom behaviour.

Bug: 196933493
Test: atest android.app.cts.WallpaperInfoTest
Change-Id: I7cb104bf7dfbbe92de72e505ec31d866a59bae4a