Add an alternative scenario to EoMT `post_process_semantic_segmentation` in case `path_offsets` is None
Author: simonreise
Pull request: yes

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Fixes #42712

This PR adds a check if `path_offsets` is None to `post_process_semantic_segmentation` function of EoMT image processors.

If `path_offsets` is not None, it executes `merge_image_patches` function, and if it is None (which means that image was not split into patches), we just run the default image post processing scenario, same as in other vision models


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Comments:
**[For maintainers]** Suggested jobs to run (before merge)

run-slow: eomt

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