Capture Launcher icon positions by reusing UiObject2

Reuse the same UiObject2/HomeAppIcon objects
when capturing Launcher icon positions.

When invoking 'launcher.workspace.allWorkspaceIcons'
we wait for the animation to finish which makes
the test fail as we expect to capture icon positions
midway through the animation.

Test: atest LauncherFoldAnimationTest
Bug: 315163608
Bug: 296991492
Flag: EXEMPT bugfix
Change-Id: I668d15165e4c777b3be24d66ad3f7888eaca2fea