[Doc] Correct checkpoint path in Dinov2 model_docs

[ambroiseodt]

Fix checkpoint path in Dinov2 model_docs.

What does this PR do?

Fixes the wrong checkpoint path in Dinov2 model_docs #45431

Changes made: the previous checkpoint (google/dinov2-base-patch16-224) does not exist and has been changed to the correct one (facebook/dinov2-base).

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[github-actions]

[For maintainers] Suggested jobs to run (before merge)

run-slow: dinov2

[stevhliu]

thanks!

[HuggingFaceDocBuilderDev]

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