Update object detection guide (#30683)

* Object detection guide

* Minor update

* Minor updates, links

* Fix typo

* Wording, add albu space

* Add missing part

* Update docs/source/en/tasks/object_detection.md

Co-authored-by: amyeroberts <[email protected]>

* Update docs/source/en/tasks/object_detection.md

Co-authored-by: NielsRogge <[email protected]>

* Update docs/source/en/tasks/object_detection.md

Co-authored-by: NielsRogge <[email protected]>

* Fix device, add imports for inference

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Co-authored-by: amyeroberts <[email protected]>
Co-authored-by: NielsRogge <[email protected]>