fix(nyz): fix pyyaml higher version compatibility bug

setup.py

@@ -49,7 +49,7 @@ setup(
         'six',
         'gym==0.20.0',  # pypy incompatible
         'torch>=1.3.1,<=1.9.0',  # PyTorch 1.9.0 is available, if some errors, you need to do something like https://github.com/opendilab/DI-engine/discussions/81
-        'pyyaml',
+        'pyyaml<6.0',
         'easydict==1.9',
         'tensorboardX>=2.1,<=2.2',
         'matplotlib',  # pypy incompatible