fix a bug

paddlepalm/_downloader.py

@@ -33,7 +33,7 @@ ssl._create_default_https_context = ssl._create_unverified_context
 _items = {
     'pretrain': {'ernie-en-uncased-large': 'https://ernie.bj.bcebos.com/ERNIE_Large_en_stable-2.0.0.tar.gz',
                  'bert-en-uncased-large': 'https://bert-models.bj.bcebos.com/uncased_L-24_H-1024_A-16.tar.gz',
-                 'bert-en-uncased-base': 'https://bert-models.bj.bcebos.com/uncased_L-12_H-768_A-12.tar.gz'
+                 'bert-en-uncased-base': 'https://bert-models.bj.bcebos.com/uncased_L-12_H-768_A-12.tar.gz',
                  'utils': None},
     'reader': {'utils': None},
     'backbone': {'utils': None},