fix ModuleNotFoundError: No module named 'paddleseg.utils.env'

[gouzil]

修复问题:

Traceback (most recent call last):
  File "setup.py", line 19, in <module>
    import paddleseg
  File "/home/aistudio/paddle_nnformer/paddleseg/__init__.py", line 15, in <module>
    from . import models, datasets, transforms
  File "/home/aistudio/paddle_nnformer/paddleseg/models/__init__.py", line 15, in <module>
    from .backbones import *
  File "/home/aistudio/paddle_nnformer/paddleseg/models/backbones/__init__.py", line 15, in <module>
    from .hrnet import *
  File "/home/aistudio/paddle_nnformer/paddleseg/models/backbones/hrnet.py", line 21, in <module>
    from paddleseg.cvlibs import manager, param_init
  File "/home/aistudio/paddle_nnformer/paddleseg/cvlibs/__init__.py", line 17, in <module>
    from .config import Config
  File "/home/aistudio/paddle_nnformer/paddleseg/cvlibs/config.py", line 24, in <module>
    from paddleseg.utils import logger
  File "/home/aistudio/paddle_nnformer/paddleseg/utils/__init__.py", line 18, in <module>
    from .env import seg_env, get_sys_env
ModuleNotFoundError: No module named 'paddleseg.utils.env'