taskStandard: don't try to call .encode on unistrings
taskStandard: don't try to call .encode on unistrings

Refs #9310.

sevein/archivematica,eckardm/archivematica,artefactual/archivematica,eckardm/archivematica,eckardm/archivematica,eckardm/archivematica,sevein/archivematica,artefactual/archivematica,sevein/archivematica,artefactual/archivematica,sevein/archivematica,artefactual/archivematica