[Feature] Add RotatedCocoMetric

[liuyanyi]

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Motivation

From https://github.com/facebookresearch/detectron2/blob/main/detectron2/evaluation/rotated_coco_evaluation.py

Use case: cfg:

test_evaluator = dict(type='RotatedCocoMetric', metric='bbox')

result:

10/19 21:14:02 - mmengine - INFO - Converting ground truth to coco format...
loading annotations into memory...
Done (t=0.09s)
creating index...
index created!
10/19 21:14:02 - mmengine - INFO - Evaluating bbox...
Loading and preparing results...
DONE (t=0.49s)
creating index...
index created!
Running per image evaluation...
Evaluate annotation type *bbox*
DONE (t=3.21s).
Accumulating evaluation results...
DONE (t=0.15s).
 Average Precision  (AP) @[ IoU=0.50:0.95 | area=   all | maxDets=100 ] = 0.635
 Average Precision  (AP) @[ IoU=0.50      | area=   all | maxDets=1000 ] = 0.948
 Average Precision  (AP) @[ IoU=0.75      | area=   all | maxDets=1000 ] = 0.757
 Average Precision  (AP) @[ IoU=0.50:0.95 | area= small | maxDets=1000 ] = 0.202
 Average Precision  (AP) @[ IoU=0.50:0.95 | area=medium | maxDets=1000 ] = 0.516
 Average Precision  (AP) @[ IoU=0.50:0.95 | area= large | maxDets=1000 ] = 0.665
 Average Recall     (AR) @[ IoU=0.50:0.95 | area=   all | maxDets=100 ] = 0.705
 Average Recall     (AR) @[ IoU=0.50:0.95 | area=   all | maxDets=300 ] = 0.705
 Average Recall     (AR) @[ IoU=0.50:0.95 | area=   all | maxDets=1000 ] = 0.705
 Average Recall     (AR) @[ IoU=0.50:0.95 | area= small | maxDets=1000 ] = 0.400
 Average Recall     (AR) @[ IoU=0.50:0.95 | area=medium | maxDets=1000 ] = 0.624
 Average Recall     (AR) @[ IoU=0.50:0.95 | area= large | maxDets=1000 ] = 0.731
10/19 21:14:06 - mmengine - INFO - Epoch(test) [453/453]  r_coco/bbox_mAP: 0.6350  r_coco/bbox_mAP_50: 0.9480  r_coco/bbox_mAP_75: 0.7570  r_coco/bbox_mAP_s: 0.2020  r_coco/bbox_mAP_m: 0.5160  r_coco/bbox_mAP_l: 0.6650

Modification

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BC-breaking (Optional)

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Use cases (Optional)

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Checklist

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2. The modification is covered by complete unit tests. If not, please add more unit test to ensure the correctness.
3. The documentation has been modified accordingly, like docstring or example tutorials.