[DocsUI]: Fix testClickRecentM3 test.

The docked search bar only is visible when show_docked_search_m3 flag is
on. Thus the test takes it into account when deciding what to check.

Bug: 428577639
Test: atest DocumentsUIUnitTests
Flag: com.android.documentsui.flags.use_material3
Change-Id: Ie547cf6c8c2fa3fa09bff0a04ebdd1e66b199a8d