Being on a hill complicates things a bit.
Some people speed up and try to blast past the dog, but I don't have enough confidence in my ability to do that, so I usually slow down and prepare to stop if necessary and use my deterrents (horn and water bottle).
At the first sign of trouble, I blast my small marine air horn. That works about 75% of the time. The next step would be a squirt in the face from my water bottle. That usually works pretty well.
I have had to stop just to keep the dog from running in front or into the side of my wheel. I've seen that happen to a rider twice, and I would rather stop than take a chance on that happening. I can always put the bike between me and the dog if necessary.
If you have never seen that dog on the route before, it might be a one time thing where it accidentally got out. I'd give it another try and just be watchful and prepared to squirt it or whatever if you see it again. I have found that dogs that chase cyclists usually don't live a long, happy life as they tend to also chase cars, and they don't usually win in those encounters.
Another option, if you can tell what house the dog belongs to, is talk to the owner or leave a note in their mailbox.