Reddit thinks it might be a tomato. I thought it was chives, obviously it's not, but I still think I picked it from the herb shelf, not from a vegetable shelf.
It does look like a tomato. The easy way to tell for sure is to gently rub the leaves -- even at that size, tomato should have a distinctive aroma. If you used compost in your potting soil, you could just have gotten a volunteer from a stray seed.
As mentioned in the comments, the seedling to the right of the tomato could be a chive. They grow fairly slowly, so "doing absolutely nothing" is par for the course.