Just let it heal naturally.

I also threated the wounds, of mostly WC animals who scratcht themselfs since the aren't used to being locked up.
But just letting them rest is maybe even better.
With handling the frog, you stress them out wich isn't reccomended as well.
When you look at WC treefrogs you often see all kind of scars on mostly the head and back.
Just let it settle if the cuts are as small as it looks like in this case.
Only when you notice it getting infected you need to treath it.