[cleanup/marian] pipelines test and new kwarg
avoids DeprecationWarning (because `max_len` kwarg is being deprecated)
# [Codecov](https://codecov.io/gh/huggingface/transformers/pull/4812?src=pr&el=h1) Report
> Merging [#4812](https://codecov.io/gh/huggingface/transformers/pull/4812?src=pr&el=desc) into [master](https://codecov.io/gh/huggingface/transformers/commit/875288b344d2181b789746e27e7b5bc62df8cae1&el=desc) will **decrease** coverage by `0.02%`.
> The diff coverage is `n/a`.

[![Impacted file tree graph](https://codecov.io/gh/huggingface/transformers/pull/4812/graphs/tree.svg?width=650&height=150&src=pr&token=9qOlN6Hb1c)](https://codecov.io/gh/huggingface/transformers/pull/4812?src=pr&el=tree)

```diff
@@            Coverage Diff             @@
##           master    #4812      +/-   ##
==========================================
- Coverage   76.18%   76.15%   -0.03%     
==========================================
  Files         128      128              
  Lines       21497    21497              
==========================================
- Hits        16377    16371       -6     
- Misses       5120     5126       +6     
```


| [Impacted Files](https://codecov.io/gh/huggingface/transformers/pull/4812?src=pr&el=tree) | Coverage Δ | |
|---|---|---|
| [src/transformers/tokenization\_marian.py](https://codecov.io/gh/huggingface/transformers/pull/4812/diff?src=pr&el=tree#diff-c3JjL3RyYW5zZm9ybWVycy90b2tlbml6YXRpb25fbWFyaWFuLnB5) | `92.79% <ø> (ø)` | |
| [src/transformers/modeling\_openai.py](https://codecov.io/gh/huggingface/transformers/pull/4812/diff?src=pr&el=tree#diff-c3JjL3RyYW5zZm9ybWVycy9tb2RlbGluZ19vcGVuYWkucHk=) | `80.00% <0.00%> (-1.36%)` | :arrow_down: |
| [src/transformers/file\_utils.py](https://codecov.io/gh/huggingface/transformers/pull/4812/diff?src=pr&el=tree#diff-c3JjL3RyYW5zZm9ybWVycy9maWxlX3V0aWxzLnB5) | `73.85% <0.00%> (-0.42%)` | :arrow_down: |
| [src/transformers/tokenization\_utils.py](https://codecov.io/gh/huggingface/transformers/pull/4812/diff?src=pr&el=tree#diff-c3JjL3RyYW5zZm9ybWVycy90b2tlbml6YXRpb25fdXRpbHMucHk=) | `89.68% <0.00%> (-0.12%)` | :arrow_down: |

------

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> `Δ = absolute <relative> (impact)`, `ø = not affected`, `? = missing data`
> Powered by [Codecov](https://codecov.io/gh/huggingface/transformers/pull/4812?src=pr&el=footer). Last update [875288b...b7b9470](https://codecov.io/gh/huggingface/transformers/pull/4812?src=pr&el=lastupdated). Read the [comment docs](https://docs.codecov.io/docs/pull-request-comments).
