Fix the misaligned pipeline usage in dreamshaper docstrings

[kirill-fedyanin]

What does this PR do?

Fixes # (issue)
There was misalignment in docstring example between import and usage.
If use the DiffusionPipeline, it would fail with "unexpected argument image" error, but with AutoPipelineForImage2Image, which states in current import, it works fine

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• [v] This PR fixes a typo or improves the docs (you can dismiss the other checks if that's the case).
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[HuggingFaceDocBuilderDev]

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

[patrickvonplaten]

Thanks!