Update README.md

Author: derronqi

README.md

@@ -4,7 +4,7 @@
 | ----------| ---------- | ----- | ------ | ----- | -------------- | -------- |
 | yolov8n   | 640        | 94.5  | 92.2   | 79.0  |  -             |  [google](https://drive.google.com/file/d/1qcr9DbgsX3ryrz2uU8w4Xm3cOrRywXqb/view?usp=sharing)       |
 | yolov8s   | 640        | 96.0  | 94.2   | 82.6  |  -             | -       | 
-| yolov8m   | 640        | -     | -      | -     |  -             | -       |
+| yolov8m   | 640        | 96.6  | 95.0   | 84.1  |  -             | -       |
 | yolov8x   | 640        | -     | -      | -     |  -             | -       |