Make format consistent with that of PreTrainedTokenizer
# [Codecov](https://codecov.io/gh/huggingface/transformers/pull/3022?src=pr&el=h1) Report
> :exclamation: No coverage uploaded for pull request base (`master@c913eb9`). [Click here to learn what that means](https://docs.codecov.io/docs/error-reference#section-missing-base-commit).
> The diff coverage is `100%`.

[![Impacted file tree graph](https://codecov.io/gh/huggingface/transformers/pull/3022/graphs/tree.svg?width=650&token=9qOlN6Hb1c&height=150&src=pr)](https://codecov.io/gh/huggingface/transformers/pull/3022?src=pr&el=tree)

```diff
@@            Coverage Diff            @@
##             master    #3022   +/-   ##
=========================================
  Coverage          ?   77.26%           
=========================================
  Files             ?       98           
  Lines             ?    16040           
  Branches          ?        0           
=========================================
  Hits              ?    12393           
  Misses            ?     3647           
  Partials          ?        0
```


| [Impacted Files](https://codecov.io/gh/huggingface/transformers/pull/3022?src=pr&el=tree) | Coverage Δ | |
|---|---|---|
| [src/transformers/tokenization\_utils.py](https://codecov.io/gh/huggingface/transformers/pull/3022/diff?src=pr&el=tree#diff-c3JjL3RyYW5zZm9ybWVycy90b2tlbml6YXRpb25fdXRpbHMucHk=) | `91.57% <100%> (ø)` | |

------

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> `Δ = absolute <relative> (impact)`, `ø = not affected`, `? = missing data`
> Powered by [Codecov](https://codecov.io/gh/huggingface/transformers/pull/3022?src=pr&el=footer). Last update [c913eb9...34be93e](https://codecov.io/gh/huggingface/transformers/pull/3022?src=pr&el=lastupdated). Read the [comment docs](https://docs.codecov.io/docs/pull-request-comments).
<|||||>This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.
