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

Beep boop, I am a bot from Hugging Face's automatic model evaluator 👋!\
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-eval-billsum-default-dd03f7-1519455003).\
Accept this pull request to see the results displayed on the [Hub leaderboard](https://huggingface.co/spaces/autoevaluate/leaderboards?dataset=billsum).\
Evaluate your model on more datasets [here](https://huggingface.co/spaces/autoevaluate/model-evaluator?dataset=billsum).

README.md

@@ -252,6 +252,39 @@ model-index:
       type: gen_len
       value: 212.8243
       verified: true
+  - task:
+      type: summarization
+      name: Summarization
+    dataset:
+      name: billsum
+      type: billsum
+      config: default
+      split: test
+    metrics:
+    - name: ROUGE-1
+      type: rouge
+      value: 42.1065
+      verified: true
+    - name: ROUGE-2
+      type: rouge
+      value: 15.4079
+      verified: true
+    - name: ROUGE-L
+      type: rouge
+      value: 24.8814
+      verified: true
+    - name: ROUGE-LSUM
+      type: rouge
+      value: 36.0375
+      verified: true
+    - name: loss
+      type: loss
+      value: 1.9130958318710327
+      verified: true
+    - name: gen_len
+      type: gen_len
+      value: 179.2184
+      verified: true
 ---
 
 # pszemraj/pegasus-x-large-book-summary