PyUpgrade 3.8 updates (#15941)

Co-authored-by: UltralyticsAssistant <web@ultralytics.com>

ultralytics/engine/predictor.py

@@ -328,7 +328,7 @@ class BasePredictor:
             frame = int(match[1]) if match else None  # 0 if frame undetermined
 
         self.txt_path = self.save_dir / "labels" / (p.stem + ("" if self.dataset.mode == "image" else f"_{frame}"))
-        string += "%gx%g " % im.shape[2:]
+        string += "{:g}x{:g} ".format(*im.shape[2:])
         result = self.results[i]
         result.save_dir = self.save_dir.__str__()  # used in other locations
         string += f"{result.verbose()}{result.speed['inference']:.1f}ms"