Add evaluation results on the default config of xsum

Beep boop, I am a bot from Hugging Face's automatic model evaluator 👋!\
Your model has been evaluated on the default config of the [xsum](https://huggingface.co/datasets/xsum) dataset by

@grapplerulrich
, using the predictions stored [here](https://huggingface.co/datasets/autoevaluate/autoeval-staging-eval-project-xsum-9818ea4b-12975766).\
Accept this pull request to see the results displayed on the [Hub leaderboard](https://huggingface.co/spaces/autoevaluate/leaderboards?dataset=xsum).\
Evaluate your model on more datasets [here](https://huggingface.co/spaces/autoevaluate/model-evaluator?dataset=xsum).

README.md

@@ -7,6 +7,42 @@ datasets:
 - cnn_dailymail
 - xsum
 thumbnail: https://huggingface.co/front/thumbnails/distilbart_medium.png
+model-index:
+- name: sshleifer/distilbart-xsum-12-6
+  results:
+  - task:
+      type: summarization
+      name: Summarization
+    dataset:
+      name: xsum
+      type: xsum
+      config: default
+      split: test
+    metrics:
+    - name: ROUGE-1
+      type: rouge
+      value: 45.2877
+      verified: true
+    - name: ROUGE-2
+      type: rouge
+      value: 22.3329
+      verified: true
+    - name: ROUGE-L
+      type: rouge
+      value: 37.3582
+      verified: true
+    - name: ROUGE-LSUM
+      type: rouge
+      value: 37.3533
+      verified: true
+    - name: loss
+      type: loss
+      value: 2.4249231815338135
+      verified: true
+    - name: gen_len
+      type: gen_len
+      value: 23.7987
+      verified: true
 ---
 
 ### Usage