Add clause to export_sms_csv.sh that excludes corrupted clips

Created by: msb

It appears that there are a small number of original archived sources in SMS that are corrupted. The table corrupted_clips has been created and populated with the clip ids of these sources. This PR adds a SQL clause to export_sms_csv.sh that excludes these clips. This will allow one of the other transcoded sources to be tried instead.

related to: uisautomation/media-webapp/issues/225