Accession Import col fix, refs #11993
Accession Import col fix, refs #11993

Remove reference (&) from $self param to addColumnHandler. Passing $self
as a reference was preventing the column handler functions from running.

This change will allow the correct import of the accession columns:
- acquisitionDate
- resourceType
- acquisitionType
- processingStatus
- processingPriority

artefactual/atom,artefactual/atom,artefactual/atom