[Pipeline] AnimateDiff SDXL (#6721)
* update conversion script to handle motion adapter sdxl checkpoint
* add animatediff xl
* handle addition_embed_type
* fix output
* update
* add imports
* make fix-copies
* add decode latents
* update docstrings
* add animatediff sdxl to docs
* remove unnecessary lines
* update example
* add test
* revert conv_in conv_out kernel param
* remove unused param addition_embed_type_num_heads
* latest IPAdapter impl
* make fix-copies
* fix return
* add IPAdapterTesterMixin to tests
* fix return
* revert based on suggestion
* add freeinit
* fix test_to_dtype test
* use StableDiffusionMixin instead of different helper methods
* fix progress bar iterations
* apply suggestions from review
* hardcode flip_sin_to_cos and freq_shift
* make fix-copies
* fix ip adapter implementation
* fix last failing test
* make style
* Update docs/source/en/api/pipelines/animatediff.md
Co-authored-by: Dhruv Nair <dhruv.nair@gmail.com>
* remove todo
* fix doc-builder errors
---------
Co-authored-by: Dhruv Nair <dhruv.nair@gmail.com>
