Fix missing return_dict in RAG example to use a custom knowledge source
We did some changes regarding the output of models but didn't change the return_dict parameter of this RAG example script.
It works as expected now
@lhoestq 

What the version of transformers you have used in this PR? <|||||>Hi !
The one on the master branch<|||||>> Hi !
> The one on the master branch

So you have installed from sources, right **(Version: 4.0.0.dev0)**? I tried to execute **use_own_knowledge_dataset.py** with your [previous PR](https://github.com/huggingface/transformers/pull/8585).  But I got the following error.  Seems like **question_enc_outputs** is not a dict but just the tensor. 

`/transformers/src/transformers/models/rag/modeling_rag.py", line 628, in forward
    question_enc_hidden_states = question_enc_outputs.hidden_states
AttributeError: 'tuple' object has no attribute 'hidden_states'`


<|||||>Thanks for letting me know ! I'll fix that as well :) <|||||>Perfect. Btw it works perfectly for version 3.4.0.

On Thu, Nov 19, 2020, 23:20 Quentin Lhoest <notifications@github.com> wrote:

> Thanks for letting me know ! I'll fix that as well :)
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