TranscriptionEntity.length should at least be 1

Having a length of 0 makes no sense here.

added 1 deleted label

No length at 0 in prod

arkindex_prod=# select count(id) from documents_transcriptionentity where length = 0;
 count
-------
     0
(1 row)

mentioned in merge request !1327 (merged)

mentioned in commit a9fe5a24

closed