Fix bf15/fp16 for pipeline_wan_vace.py

[SlimRG]

What does this PR do?

Fix problem with vae, when vae's dtype != float32

Fixes #12141

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Who can review?

@yiyixuxu and @asomoza

Maybe:
@DN6 @a-r-r-o-w
@sayakpaul @yiyixuxu

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[SlimRG]

Make fix in single line as you wanted =)

[a-r-r-o-w]

There's one line above the line you added that also performs a dtype cast and is now redundant. Could you remove that?

[SlimRG]

There's one line above the line you added that also performs a dtype cast and is now redundant. Could you remove that?

There's one line above the line you added that also performs a dtype cast and is now redundant. Could you remove that?

Done

[a-r-r-o-w]

thanks!

[HuggingFaceDocBuilderDev]

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[a-r-r-o-w]

@SlimRG I pushed a change because I believe your PR fixes a failing test we've had for a while marked xfail. With this change, things pass locally so waiting to see if it passes on our CI as well

[a-r-r-o-w]

Okay perfect, it passes!