[EmployeeDirectory] Fix null reference exception
[EmployeeDirectory] Fix null reference exception

Then 'Also show teachers w/o disciplines' flag is set and there are no edu. levels selected,
EduProgramProfileRepository.GetEduProgramProfiles_ByEduLevels is fires null reference exception
caused by empty IN () brackets in SQL query.

roman-yagodin/R7.University,roman-yagodin/R7.University,roman-yagodin/R7.University