Fix bug when name of uploading key has white space
Fix bug when name of uploading key has white space

Change 'urllib.quote_plus' to 'urllib.quote'. Here we need to
encode white space ' ' to '%20'. Using 'urllib.quote_plus'
leads to 'signature_not_match'.

markduan/qingcloud-sdk-python,Xuanwo/qingcloud-sdk-python,yunify/qingcloud-sdk-python