The TurboTax interview is complicated* and it's easy to make mistakes. If you know your refund is not taxable, just don't enter it (or change it to 0), or check the box that says you used the standard deduction last year.
Lying to TurboTax to get it to do what you want does not constitute lying to the IRS.
*Particular to your situation, there is a screen where you need to indicate that the box on line 5a (option to deduct sales tax) of last year's Schedule A is checked
