add in layer tf clip text tokenizer
Author: piEsposito
Pull request: yes

# What does this PR do?

- Adds in layer `TFCLIPTokenizer` to enable serialization and serving it with TF Serving

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Addresses first step of #19992 


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Models:

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Comments:
Just need to figure out where to append `eos_token` and `bos_token` within the tokenizers.

cc @Rocketknight1 so it's on your radar when the PR is ready :-) 

The docs for this PR live [here](https://moon-ci-docs.huggingface.co/docs/transformers/pr_20626). All of your documentation changes will be reflected on that endpoint.

Clip `</w>` formatting is too cursed, I'm thinking of jump ship and do the tokenizer from Roberta instead haha.

I was gonna jump ship, but then this absolute beast @pedrogengo came in and found a magic way to make it work. Making him a coauthor of the PR bc of that.

We are not supporting batches (yet).

We now have batch tokenization implemented and working :)

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We are still working on it!

This issue has been automatically marked as stale because it has not had recent activity. If you think this still needs to be addressed please comment on this thread.

Please note that issues that do not follow the [contributing guidelines](https://github.com/huggingface/transformers/blob/main/CONTRIBUTING.md) are likely to be ignored.

Did this ever get resolved?

This issue has been automatically marked as stale because it has not had recent activity. If you think this still needs to be addressed please comment on this thread.

Please note that issues that do not follow the [contributing guidelines](https://github.com/huggingface/transformers/blob/main/CONTRIBUTING.md) are likely to be ignored.