Fix yaml.safe_load() ignore emoji errors (#5060)

models/yolo.py

@@ -87,7 +87,7 @@ class Model(nn.Module):
         else:  # is *.yaml
             import yaml  # for torch hub
             self.yaml_file = Path(cfg).name
-            with open(cfg) as f:
+            with open(cfg, errors='ignore') as f:
                 self.yaml = yaml.safe_load(f)  # model dict
 
         # Define model