Add warning emoji ⚠️ on --conf > 0.001 (ultralytics#8005)

* Add warning emoji on `--conf > 0.001`

* Update val.py

val.py

@@ -38,7 +38,7 @@
 from utils.callbacks import Callbacks
 from utils.dataloaders import create_dataloader
 from utils.general import (LOGGER, check_dataset, check_img_size, check_requirements, check_yaml,
-                           coco80_to_coco91_class, colorstr, increment_path, non_max_suppression, print_args,
+                           coco80_to_coco91_class, colorstr, emojis, increment_path, non_max_suppression, print_args,
                            scale_coords, xywh2xyxy, xyxy2xywh)
 from utils.metrics import ConfusionMatrix, ap_per_class, box_iou
 from utils.plots import output_to_target, plot_images, plot_val_study
@@ -368,7 +368,7 @@ def main(opt):
 
     if opt.task in ('train', 'val', 'test'):  # run normally
         if opt.conf_thres > 0.001:  # https://github.com/ultralytics/yolov5/issues/1466
-            LOGGER.info(f'WARNING: confidence threshold {opt.conf_thres} >> 0.001 will produce invalid mAP values.')
+            LOGGER.info(emojis(f'WARNING: confidence threshold {opt.conf_thres} > 0.001 produces invalid results ⚠️'))
         run(**vars(opt))
 
     else: