Remove unnecessary wallpaper adjustment on transition

Since WallpaperController won't change wallpaper target if the
closing target is in transition, the adjustWallpaperWindows
won't change any state when transition is ready but spend the
time to traverse.

The entry points from AR#setVisibility->requestUpdateWallpaperIfNeeded
and transition finish->commitVisibility->postApplyAnimation
->FINISH_LAYOUT_REDO_WALLPAPER are already enough to update.

Bug: 258880446
Test: WallpaperControllerTests
Change-Id: I6b48099c455c2987c74b31b9d6d7d06d484a7c56