message: Fix python 3 test error caused by the difference of `b""` vs. `""`
diff: @@ -113,7 +113,7 @@ class IgnoreErrorsTest(test_base.DatasetTestBase):
  writer.close()
  # Append corrupted data
  with open(fn, "a") as f:
  - f.write(b"corrupted data")
  + f.write("corrupted data")
  dataset = readers.TFRecordDataset(filenames).apply(
  error_ops.ignore_errors())
  