Change pipeline tag

This PR changes the pipeline tag to `image-segmentation`, making sure that the model shows up in the list of all image segmentation models:
https://huggingface.co/models?pipeline_tag=image-segmentation&sort=trending.

README.md

@@ -1,7 +1,7 @@
 ---
-license: mit
-pipeline_tag: object-detection
 library_name: detectron2
+license: mit
+pipeline_tag: image-segmentation
 ---
 
 # Mr. DETR: Instructive Multi-Route Training for Detection Transformers
@@ -28,6 +28,4 @@ Existing methods enhance the training of detection transformers by incorporating
 
 ## Performance
 [Demo Video for Street](https://www.bilibili.com/video/BV1ThZnYxE5G/?spm_id_from=333.1387.homepage.video_card.click&vd_source=3b32a049a039d0ef814f8588b3c9b2d9)  
-[Demo Video for Dense and Crowded Scene](https://www.zhihu.com/zvideo/1890060966391153546)
-
-
+[Demo Video for Dense and Crowded Scene](https://www.zhihu.com/zvideo/1890060966391153546)