ECMS-5916 Failure in TestTimelineService

Fix description:
* Restore the item limitation per timeline (5 items) in testGetDocumentsOfEarlierThisWeek()
* Correct the condition of counter for testGetDocumentsOfEarlierThisMonth() and testGetDocumentsOfEarlierThisMonth2() by taking into account the case where last week of a year is week 1.