Fix string arguments in query

[CrafterKolyan]

Check the last query in dev.jsonl for example
It'll be:

SELECT  col4 FROM table WHERE col3 = democratic AND col2 = new york AND col0 = terence j. quinn

instead of:

SELECT  col4 FROM table WHERE col3 = "democratic" AND col2 = "new york" AND col0 = "terence j. quinn"

[salesforce-cla]

Thanks for the contribution! Before we can merge this, we need @CrafterKolyan to sign the Salesforce.com Contributor License Agreement.