Add check flags rule to ensure test is skipped

Forgot to add this @Rule in a previous test and whilst trying to board
the latest train it has not stopped the test from executing on devices
which it should skip. This should fix that.

Bug: 393339189 , 377771803
Test: atest SortDocumentUiTest#testSortByArrowIcon
Flag: EXEMPT test change
Change-Id: Ib1ee43f40884d70422a7cd0b912a46eacfa28c32