Typo on markdown link in README.md
# [Codecov](https://codecov.io/gh/huggingface/transformers/pull/2698?src=pr&el=h1) Report
> Merging [#2698](https://codecov.io/gh/huggingface/transformers/pull/2698?src=pr&el=desc) into [master](https://codecov.io/gh/huggingface/transformers/commit/0aa40e9569a71306036de3a217eed55521699604?src=pr&el=desc) will **not change** coverage.
> The diff coverage is `n/a`.

[![Impacted file tree graph](https://codecov.io/gh/huggingface/transformers/pull/2698/graphs/tree.svg?width=650&token=9qOlN6Hb1c&height=150&src=pr)](https://codecov.io/gh/huggingface/transformers/pull/2698?src=pr&el=tree)

```diff
@@           Coverage Diff           @@
##           master    #2698   +/-   ##
=======================================
  Coverage   74.24%   74.24%           
=======================================
  Files          92       92           
  Lines       15215    15215           
=======================================
  Hits        11297    11297           
  Misses       3918     3918
```



------

[Continue to review full report at Codecov](https://codecov.io/gh/huggingface/transformers/pull/2698?src=pr&el=continue).
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> `Δ = absolute <relative> (impact)`, `ø = not affected`, `? = missing data`
> Powered by [Codecov](https://codecov.io/gh/huggingface/transformers/pull/2698?src=pr&el=footer). Last update [0aa40e9...9a11e6f](https://codecov.io/gh/huggingface/transformers/pull/2698?src=pr&el=lastupdated). Read the [comment docs](https://docs.codecov.io/docs/pull-request-comments).
<|||||>Great, thanks!