old data loader: blank line at the end of business_categories.csv causes duplicate key error

Reproduce:

cd core-content/import_scripts_cumberland/business_taxonomy
cp /tmp/UK\ AML\ business_categories.csv business_categories.csv
./load_business_categories.sh <db username> <db password> <db host>

You'll see an SQL exception in the output and this is what the loader DB table looks like:

select * from businessCategoryLoader;

 
| Confectionery                                | 9312 | active |        |
| Engineering                                  | 9313 | active |        |
|                                              | 9313 |        |        |
+----------------------------------------------+------+--------+--------+

load_business_categories.sql has a statement that looks like it will take care of this scenario, but for some reason the last BC ID got carried over to the blank line when it was inserted in to the database.

#Remove blank line that got loaded
delete from businessCategoryLoader where ID = '';