Added warning message when --single-cls
is used incorrectly by [#13028](https://github.com/ultralytics/yolov5/issues/13028)
#13079
Job | Run time |
---|---|
6m 22s | |
3m 12s | |
9m 53s | |
7m 0s | |
2m 47s | |
2s | |
29m 16s |