Allow some information to be different when there are multiple specimen tubes for a single case
When importing specimen information from JSON files, there is the possibility to match against an existing NoSpecimen or Specimen item and copy some information from that item in case it is missing in the JSON file.
When there are multiple specimen tubes for a single case there is typically only one NoSpecimen item pre-registered. The first JSON file uses that item and converts it to a Specimen. The second JSON file can then use the existing Specimen to copy information. In most cases the information should be the same, but there are cases when it may be different. Those cases currently generate an error but should generate a warning instead.