Potential memory leak when creating tables fails

In qhelpcollectionhandler.cpp, QHelpCollectionHandler::copyCollectionFile: the QSqlQuery 'copyQuery' is allocated on the heap, but not deleted if a failure of either createTables or recreateIndexAndNamespaceFilterTables results in a premature return.

Coverity issue here:

https://scan3.coverity.com/reports.htm#v42553/p10113/fileInstanceId=32687441&defectInstanceId=8977104&mergedDefectId=21930