Fix: Obtaining cat_id through class name may cause bug in some cases

[mjq2020]

An incorrect cat_id occurs when the name of the supercategory is the same as the actual detection category name of the dataset.

Motivation

An incorrect cat_id occurs when the name of the supercategory is the same as the actual detection category name of the dataset.

Modification

When obtaining cat_id, set the sup_names of the class name at the same time to prevent the cat_id of supercategory from being returned.

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