I had always kept a police pepper spray holstered to my steering tube for quick draw defense of dog attacks.
I’m a dog lover and have a dog myself, but I will attest to the reality that some dogs behave quite differently than their owner expects or realizes when out of their watch. Our next door neighbor had a rhodesian ridgeback that apparently was the sweetest thing to all their friends and family and other visiting pets, but for unknownst reason, was super hostile to my golden retriever and then me by extension. I knew this from encountering it with their hired dog walker, but it wasn’t until a good year+ later when I ran into him on the street with our dogs, and I was trying to go the other way (we’re good friends, I normally run up to him to talk!) so there wouldn’t be a dog issue, and his dog was straining, barking, and showing full aggression to get at myself and my dog - that owner was horrified, and said “I don’t know what’s gotten into her - she’s NEVER like this, ever!”
Obviously, he didn’t see the multiple other instances that occurred before this, he genuinely had no idea. Most dogs are fairly consistent in behavior, but you do have to check before fully trusting yours on their own.
So sadly, yes, you should report dog bites to the police in general.