[Modular] support standard repo (#11944)
* make modular pipeline work with model_index.json
* up
* style
* up
* up
* style
* up more
* Fix MultiControlNet import (#12118)
fix
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Co-authored-by: Álvaro Somoza <asomoza@users.noreply.github.com>
Co-authored-by: Dhruv Nair <dhruv.nair@gmail.com>
