Update configuration_bart.py
Updated bart config in accordance with this issue:
![image](https://user-images.githubusercontent.com/49692939/195330903-af849c7a-b711-4c9d-93e3-f6612c2413ec.png)

Tests passed
![image](https://user-images.githubusercontent.com/49692939/195330933-b984cac2-d74e-4a86-9e81-fca680586123.png)


_The documentation is not available anymore as the PR was closed or merged._