Fix MBart failing test

[LysandreJik]

Fixes the failing test by adjusting the expected sentence. The sentence turns from

[...] will only worsen the violence and misery of millions.

to

[...] only make violence and misery worse for millions of people.

which seems grammatically correct still. @patrickvonplaten please let me know if you think this is a real issue or not.

[patrickvonplaten]

Thanks for fixing this test - this was actually failing since a long time and no-one fixed it