OmDet Turbo processor standardization

[qubvel]

What does this PR do?

Standardize post-processing for OmDet Turbo model (see #34926 for more info)

1. Rename score_threshold to threshold argument in post_process_grounded_object_detection
2. Rename classes to text_labels argument in post_process_grounded_object_detection and make it optional
3. Rename classes key to text_labels in post-processed output dictionary
4. Add labels (class indexes) key to post-processed output dictionary

The signature is going to be:

    def post_process_grounded_object_detection(
        self,
        outputs: "OmDetTurboObjectDetectionOutput",
        text_labels: Optional[Union[List[str], List[List[str]]]] = None,           # <--------- renamed: classes -> text_labels + Optional now
        threshold: float = 0.3,                                                    # <--------- renamed: score_threshold -> threshold
        nms_threshold: float = 0.5,
        target_sizes: Optional[Union[TensorType, List[Tuple]]] = None,
        max_num_det: Optional[int] = None,
    )

The output is going to be:

[
  {
      "boxes": torch.tensor of shape (N, 4),
      "labels": torch.tensor of shape (N,),                                       # <-------- new key, int indices, consistent with other object detection outputs
      "scores": torch.tensor of shape (N,),
      "text_labels": list of str names of len N (previously classes) or `None`    # <-------- renamed: classes -> text_labels
  },
  ...
]

"classes" key is also available, it will return text_labels and issue a warning

TODO:

• Add deprecation for dict key

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[qubvel]

cc @yonigozlan for review if you have bandwidth

[yonigozlan]

Looks much better thanks for refactoring! 🤗

[qubvel]

@ArthurZucker please review when you have bandwidth

[ArthurZucker]

Thanks 🤗 sorry for the delay

[ArthurZucker]

let's use camel casing please!

[qubvel]

Fixed in 2d7a6b2

[ArthurZucker]

not 100% we need this (the class is a bit over engineered) but alright