[Fix] Fix confusion_matrix

[liuyanyi]

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Motivation

#869

Modification

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BC-breaking (Optional)

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Checklist

1. Pre-commit or other linting tools are used to fix the potential lint issues.
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.

[zytx121]

LGTM

[notbug1024]

Hello, when I used a data set in dota format to experiment with rotating frames, I encountered the same problem as the #869 , but I solved it according to the method provided below.

However, when I experimented with the coco format data set, an error still occurred. The specific error information is as follows. How should I solve it? Thanks.

File "/mnt/chen2t/mmrotate-1.0.0rc1/tools/analysis_tools/confusion_matrix_modify.py", line 276, in
main()
File "/mnt/chen2t/mmrotate-1.0.0rc1/tools/analysis_tools/confusion_matrix_modify.py", line 263, in main
confusion_matrix = calculate_confusion_matrix(dataset, results,
File "/mnt/chen2t/mmrotate-1.0.0rc1/tools/analysis_tools/confusion_matrix_modify.py", line 88, in calculate_confusion_matrix
analyze_per_img_dets(confusion_matrix, gts, res_bboxes, score_thr,
File "/mnt/chen2t/mmrotate-1.0.0rc1/tools/analysis_tools/confusion_matrix_modify.py", line 129, in analyze_per_img_dets
gt_bboxes = qbox2rbox(gt_bboxes)
File "/mnt/chen2t/mmrotate-1.0.0rc1/mmrotate/structures/bbox/box_converters.py", line 109, in qbox2rbox
points = boxes.cpu().numpy().reshape(-1, 4, 2)
ValueError: cannot reshape array of size 4 into shape (4,2)