Don't use Pine Sol. Or Lestoil. Or Murphy's Oil Soap.
Reason for all 3 is the same. They all have oil as an ingredient for cleaning. Grout absorbs oil and it stays inside the grout.
Pine Sol does not have much pine oil. But why have any?
There are lots of good neutral cleaners that will not stain the grout at all.
Why, you might even, if you're lucky, be able to buy some of them from this very website!