Fix doc link in README
close https://github.com/huggingface/transformers/issues/2252

- [x] Update `.circleci/deploy.sh`
- [x] Update `deploy_multi_version_doc.sh`

Set commit hash before "Release: v2.3.0".

# [Codecov](https://codecov.io/gh/huggingface/transformers/pull/2264?src=pr&el=h1) Report
> Merging [#2264](https://codecov.io/gh/huggingface/transformers/pull/2264?src=pr&el=desc) into [master](https://codecov.io/gh/huggingface/transformers/commit/645713e2cb8307e41febb2b7c9f6036f6645efce?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/2264/graphs/tree.svg?width=650&token=9qOlN6Hb1c&height=150&src=pr)](https://codecov.io/gh/huggingface/transformers/pull/2264?src=pr&el=tree)

```diff
@@           Coverage Diff           @@
##           master    #2264   +/-   ##
=======================================
  Coverage   78.35%   78.35%           
=======================================
  Files         133      133           
  Lines       19878    19878           
=======================================
  Hits        15576    15576           
  Misses       4302     4302
```



------

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> `Δ = absolute <relative> (impact)`, `ø = not affected`, `? = missing data`
> Powered by [Codecov](https://codecov.io/gh/huggingface/transformers/pull/2264?src=pr&el=footer). Last update [645713e...9d00f78](https://codecov.io/gh/huggingface/transformers/pull/2264?src=pr&el=lastupdated). Read the [comment docs](https://docs.codecov.io/docs/pull-request-comments).
<|||||>Thanks @upura!