Fixing up some logic around excluded tasks

- We already check for the excluded task flag in isInVisibleRange, so we
  should handle skipping that check in there. This fixes the issue where
  an excluded task behind a non-visible task would still fail to show
  even if it was the last visible task.

Bug: 125475435
Test: atest WmTests:RecentTasksTest
Change-Id: I26e79197c3d2bda30f597dd7d4fa879784f14dc8