MaskFormer post_process_instance_segmentation bug fix convert out side of loop

[amyeroberts]

What does this PR do?

Resolves a bug in post processing logic in MaskFormer and Mask2Former.

If return_coco_annotation is set to True the generated segmentation map was converted to RLE before finishing iterating over all of the queries. This breaks the assumption that segmentation is an array of the same shape as pred_masks here in the for loop.

Fixes #25486

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[HuggingFaceDocBuilderDev]

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

[sgugger]

Thanks for the fix!

[MayChi22]

Hi,
I am using transformers Version: 4.32.0.dev0,
do you have an estimated time to release a version with this fix?
thanks

[amyeroberts]

@MayChi22 We release a new version roughly every month, so there will likely be a new release in a few weeks.