Add evaluation results on the default config and test split of billsum

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Your model has been evaluated on the default config and test split of the [billsum](https://huggingface.co/datasets/billsum) dataset by

@pszemraj

, using the predictions stored [here](https://huggingface.co/datasets/autoevaluate/autoeval-staging-eval-billsum-default-6d3727-15406134).\
Accept this pull request to see the results displayed on the [Hub leaderboard](https://huggingface.co/spaces/autoevaluate/leaderboards?dataset=billsum).\
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README.md

@@ -243,6 +243,39 @@ model-index:
       type: gen_len
       value: 65.4005
       verified: true
+  - task:
+      type: summarization
+      name: Summarization
+    dataset:
+      name: billsum
+      type: billsum
+      config: default
+      split: test
+    metrics:
+    - name: ROUGE-1
+      type: rouge
+      value: 40.5843
+      verified: true
+    - name: ROUGE-2
+      type: rouge
+      value: 17.3401
+      verified: true
+    - name: ROUGE-L
+      type: rouge
+      value: 25.1256
+      verified: true
+    - name: ROUGE-LSUM
+      type: rouge
+      value: 34.6619
+      verified: true
+    - name: loss
+      type: loss
+      value: 4.792657375335693
+      verified: true
+    - name: gen_len
+      type: gen_len
+      value: 163.9394
+      verified: true
 ---
 
 # Longformer Encoder-Decoder (LED) fine-tuned on Booksum