refine code

Author: JiayiFeng

python/paddle/fluid/tests/unittests/test_multi_pass_reader.py

@@ -61,6 +61,5 @@ def test_main(self):
                 img_val, = exe.run(fetch_list=[img])
                 batch_count += 1
                 self.assertLessEqual(img_val.shape[0], self.batch_size)
-                print(batch_count)
             data_file.reset()
             self.assertEqual(batch_count, self.num_batch * self.pass_num)