Refactor some AppSearch cts tests.

Move testPutDocuments_emptyBytesAndDocuments to Base class.

Bug: 275629842
Test: atest CtsAppSearchTestCases CtsAppSearchHostTestCases AppSearchServicesTests AppSearchCoreTests ContactsIndexerTests
Change-Id: Ice9b74a9c42f3257f89867f1c35873b1502027a3
5 files changed