Yup, a warm washcloth to clean it, and then leave it be. It should be fine. Rats heal very fast, so I wouldn't be shocked if it happened today! Neosporin is OK (just not the kind with pain reliever in it), and what we normally recommend is that you put it on, keep her (and her sister) distracted for about 5 minutes, at which point all the good stuff will have soaked in as much as it's going to, and you can wipe off the extra.

But, she may not need it. Hopefully she'll heal up quick with no abscesses!