Add run_mim_no_trainer.py example script
Author: Saad135
Pull request: yes

# What does this PR do?

Adds a no_trainer example script for image pretraining.

Relates to https://github.com/huggingface/transformers/issues/20053

@NielsRogge, It is still incomplete but could you please have a look at the code so far to see if something needs to be changed :-)

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Models:

- albert, bert, xlm: @LysandreJik
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Comments:
The docs for this PR live [here](https://moon-ci-docs.huggingface.co/docs/transformers/pr_20412). All of your documentation changes will be reflected on that endpoint.

@NielsRogge can I get some feedback on the code so far. Thanks :-). Could you also tell me if there are any specific tests that I need to run for this case.

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@NielsRogge friendly ping on this PR.

Hi @Saad135 the initial draft looks great already!

Let me know if you need any help finishing this PR.

Hello @NielsRogge, thank you for checking out the draft. I would appreciate if you could point me towards the next steps I should take. I mean, should I make the draft ready for review or should I run some specific tests or maybe something else? I am still quite new to OS contributions, so the next step might be a very simple one which is not apparent to me right now.

I'd recommend running both the trainer.py and no_trainer.py scripts on a small dataset and see if they progress similarly.

Once that's done, you can mark the PR as ready for review

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.

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Cc @amyeroberts, this PR should be ready for review.

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.

@Saad135  - any updates on this PR? Once feature extractor references have been updated to image processor and the check Niels suggested have been done it should be ready to merge :) 

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.

@amyeroberts This PR seems to be have been stalled and closed due to inactivity. I have taken it over in PR #23156 to complete it.