Fix Wan and Motif video pipeline fast test failures (#14269)
* Fix Wan and Motif video pipeline fast test failures
Description
This PR fixes several failing fast tests for Motif Video and Wan pipelines.
Changes
Updated test_motif_video.py to use a Motif-specific fp16 save/load tolerance.
T5Gemma2Encoder rebuilds non-persistent RoPE buffers after save/load, which introduces small fp16 numerical drift. The test now keeps coverage while allowing this expected drift.
Updated transformer_wan.py to keep Wan RoPE modules in fp32 during mixed precision handling.
This avoids fp16 precision drift in Wan save/load paths.
Updated memory.py group offloading coverage to include transformer_2 and skip None optional components.
This fixes Wan 2.2 memory/offloading tests where optional secondary transformers may be absent.
Updated stale expected slices in test_wan_image_to_video.py for:
TestWanImageToVideoPipeline::test_inference
TestWanFLFToVideoPipeline::test_inference
Signed-off-by: Wang, Yi A <yi.a.wang@intel.com>
* revert change in test_wan_image_to_video.py
Signed-off-by: Wang, Yi A <yi.a.wang@intel.com>
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Signed-off-by: Wang, Yi A <yi.a.wang@intel.com>
Co-authored-by: Sayak Paul <spsayakpaul@gmail.com>
