If an altitude report has no unique identifier, log the error instead of printing the warning

[thejunglejane]

Prior to somewhere around May 2015, Reporter didn't store uniqueIdentifiers in altitude sub-reports. To deal with this, datums will create UUIDs for altitude reports missing them. If later you try to update one of these altitude reports, datums won't be able to find the right altitude report by uniqueIdentifier and will do nothing. This is intentional. In the future, datums may use the report's uniqueIdentifier to find the right altitude sub-report as there is a one-to-one relationship.

• Document logging behavior