dev/core#2073 Fix use of legacy leaky method in tested code

dev/core#2073 Fix use of legacy leaky method in tested code

Overview
----------------------------------------
Fix use of legacy leaky method in tested code

Before
----------------------------------------
dao->query()

After
----------------------------------------
CRM_Core_DAO::executeQuery()

Technical Details
----------------------------------------
This is too low volume to really leak but it uses the leaky legacy method and
has test cover in

CRM_Contact_Page_View_UserDashboard_GroupContactTest.testBrowseDisplaysCorrectListOfAddedGroups
CRM_Contact_Page_View_UserDashboard_GroupContactTest.testBrowseDisplaysCorrectListOfAVailableGroups
CRM_Contact_Page_View_UserDashBoardTest.testDashboardContentEmptyContact
CRM_Contact_Page_View_UserDashBoardTest.testDashboardContentContributionsWithInvoicingEnabled
CRM_Contact_Page_View_UserDashBoardTest.testDashboardContentContributions

----------------------------------------