Update examples with image processors

[amyeroberts]

What does this PR do?

Updates all of the feature extractor references to image processors in the examples folder.

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[HuggingFaceDocBuilderDev]

The documentation is not available anymore as the PR was closed or merged.

[NielsRogge]

Thanks a lot for fixing! 🙏

[sgugger]

Thanks a lot!

[stas00]

This broke the deepspeed tests. Fix is here: #21283

when modifying examples and breaking back compat please scan the slow tests and adjust those too. Thank you!

The reason this is important is because Deepspeed CI runs our slow deepspeed tests as normal CI so when we break things their CI is broken.

[amyeroberts]

@stas00 - thanks for applying a quick fix and apologies about the break. I'll make sure to remember the slow tests next time!

[stas00]

Thank you, Amy!

tests/extended/ and tests/deepspeed are the ones that heavily rely on examples/pytorch