OwlViT/Owlv2 post processing standardization
Author: qubvel
Pull request: yes
Labels: name: Vision

name: run-slow

name: Processing

# What does this PR do?

Standardize OwlViT and Owlv2 post-processing

1) Add `post_process_grounded_object_detection` method for Processor (+ deprecation for `post_process_object_detection` method)

```python
def post_process_grounded_object_detection(
    self,
    outputs,
    threshold: float = ...,
    target_sizes: Optional[Union[TensorType, List[Tuple]]] = None,
    text_labels: Union[List[str], List[List[str]]] = None,  # <------------- new keyword arg
)
```

2) Add `text_labels` for post-processed output (if `text_labels` are provided as a keyword argument for `post_process_grounded_object_detection`). It's already mapped text names for detected bounding boxes.


For a full description regarding standardization see #34926

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Comments:
Hey @molbap! Please review if you have bandwidth!

The docs for this PR live [here](https://moon-ci-docs.huggingface.co/docs/transformers/pr_34929). All of your documentation changes will be reflected on that endpoint. The docs are available until 30 days after the last update.

I would prefer to leave it as separate methods. This way, it is more consistent with other post-processing methods like `post_process_object_detection`, `post_process_image_segmentation`, etc., and there is no need to overcomplicate the code with more if/else code paths.

@ArthurZucker please review when you have bandwidth