Add TAPL test for dismiss DesktopTaskView

This CL adds 2 new E2E Tapl tests for checking dismiss DesktopTaskView.
- dismissFocusedTask_thenDesktopIsCentered validates the following scenarios:
  - Scenario: When Focused Task is in the center of the screen, with 1 other task in the grid and 1 desktop task.
  - When focused task is dismissed, the next task in the grid takes its place to be the next focused task at the center of the screen.
  - When the last focused task is dismissed, the desktop task takes its place at the center of the screen.

- dismissDesktopTask_thenFocusedTaskIsCentred validates the following scenarios:
  - Scenario: When Desktop Task is in the center of the screen, with 1 focused task and 1 task in the grid.
  - When focused task is dismissed, the next task in the grid takes its place, adjacent to desktop task.
  - When desktop task is dismissed, the focused task takes its place at the center of the screen.

Fix: 353948500
Flag: com.android.launcher3.enable_large_desktop_windowing_tile
Test: TaplTestsOverviewDesktop
Change-Id: Ie2aa28cd2b30a2bf10e877721416399bcf47acf6