Fix flaky/failing two panel TAPL tests

Since Cuttlefish emulators are quite slow, some
of the two panel related TAPL tests were failing
due to multiple page changes instead of single ones.

Test: atest -c NexusLauncherTests:com.android.launcher3.ui.workspace.TwoPanelWorkspaceTest
Bug: 236136463
Fix: 252747355
Change-Id: Ib154cf97040fcea3b4d2d7082352c06de74f8c2a
(cherry picked from commit 486f7c87)
Merged-In: Ib154cf97040fcea3b4d2d7082352c06de74f8c2a