DEAR PAW’S CORNER: My dog Trey is a 3-year-old mixed breed, mostly Lab, who pulls at his leash every time we go out for a walk. I don’t want to use a choke collar, because it seems painful and counterproductive to punish him every time he tries to pull ahead. How can I get Trey to walk next to me and not tug all the time? -- Bill in New Orleans DEAR BILL: Dogs love being outside and exploring. Tha…