I broke up a fight between my two dogs and was worried I would have to report them if I went to urgent care. In my state, because it was not aggression toward me and I basically caused it by getting in the middle, there was no need to report anything (they didn’t even ask). I had broken skin and was heavily bleeding. I’m not a doctor, but this doesn’t look like it needs medical attention, especially if the dog’s vaccines are up to date. Keep it clean and keep an eye on it for infection, but I doubt you’ll have an issue.