Update benchmarks significant digits (ultralytics#7103)

Author: glenn-jocher

utils/benchmarks.py

@@ -67,7 +67,7 @@ def run(weights=ROOT / 'yolov5s.pt',  # weights path
             result = val.run(data, w, batch_size, imgsz, plots=False, device=device, task='benchmark', half=half)
             metrics = result[0]  # metrics (mp, mr, map50, map, *losses(box, obj, cls))
             speeds = result[2]  # times (preprocess, inference, postprocess)
-            y.append([name, metrics[3], speeds[1]])  # mAP, t_inference
+            y.append([name, round(metrics[3], 4), round(speeds[1], 2)])  # mAP, t_inference
         except Exception as e:
             LOGGER.warning(f'WARNING: Benchmark failure for {name}: {e}')
             y.append([name, None, None])  # mAP, t_inference