message: Fix video unit migration script
diff: @@ -44,8 +44,8 @@ class VideoUnitMigration {
  const videoUnits = await Unit.find({'__t': 'video'}).exec();
  const updatedFileUnits = await Promise.all(videoUnits.map(async(videoUnit) => {
  const videoUnitObj: IFileUnit = <IFileUnit>videoUnit.toObject();
  - videoUnitObj.fileUnitType = videoUnitObj.type;
  - videoUnitObj.type = 'file';
  + videoUnitObj.fileUnitType = videoUnitObj.__t;
  + videoUnitObj.__t = 'file';
  videoUnitObj._id = new ObjectID(videoUnitObj._id);
  const unitsAfterReplace = await mongoose.connection.collection('units')
  