Errors thrown in Occurrence download launcher should result in download being marked as failed

[djtfmartin]

This was noticed on UAT. An error was thrown:

Caused by: java.lang.RuntimeException: Unknown JSON property 'description'.
        at org.gbif.api.jackson.DownloadRequestSerde.lambda$deserialize$4(DownloadRequestSerde.java:142)
        at java.base/java.util.Iterator.forEachRemaining(Iterator.java:133)
        at org.gbif.api.jackson.DownloadRequestSerde.deserialize(DownloadRequestSerde.java:142)
        at org.gbif.api.jackson.DownloadRequestSerde.deserialize(DownloadRequestSerde.java:57)
        at com.fasterxml.jackson.databind.deser.SettableBeanProperty.deserialize(SettableBeanProperty.java:545)
        at com.fasterxml.jackson.databind.deser.BeanDeserializer._deserializeWithErrorWrapping(BeanDeserializer.java:570)
        ... 27 common frames omitted

Once this error was thrown, the download was just stuck in a PREPARING state.
The download should perhaps be marked as failed, and then attention can be given to the root cause.

[MattBlissett]

In many cases it would be preferable for the launcher to NAK the message, leaving it for later — e.g. if Airflow is temporarily unavailable, it's better than the downloads remain in the queue until it becomes available again.

If the launcher can't handle a download, I think this deserves an email notification, as we have for downloads that fail later in the process.