SegmentationModel - get proper output in postprocess()

[mgumowsk]

What does this PR do?

Using SegmentationModel with OpenVINO Model Server adapter caused ov::merge exception.
The reason is the order of the outputs.
This PR makes sure, that feature_vector is not used in postprocess() function.

[sovrasov]

@mgumowsk apparently we have some CI issues, I'll make a dummy PR to check

[sovrasov]

@mgumowsk we can merge this if it's urgent, since #144 fails on the same testcases.
I believe that happened because of a new version of ultralytics package and OV models converted with a new OV version

[mgumowsk]

@mgumowsk we can merge this if it's urgent, since #144 fails on the same testcases. I believe that happened because of a new version of ultralytics package and OV models converted with a new OV version

@sovrasov if you can then yes, please merge, without it segmentation model doesn't work in Geti.