GitLab

* document question answering guide

* Added the list of supported models

* Apply suggestions from code review
Co-authored-by: Sylvain Gugger <35901082+sgugger@users.noreply.github.com>

* switched to AutoProcessor

* feedback addressed

* Apply suggestions from code review
Co-authored-by: NielsRogge <48327001+NielsRogge@users.noreply.github.com>
Co-authored-by: Sayak Paul <spsayakpaul@gmail.com>

* Update docs/source/en/tasks/document_question_answering.mdx
Co-authored-by: Sayak Paul <spsayakpaul@gmail.com>

* more feedback addressed

* addressed comments about evaluation loss

* added appropriate image link

* make style

* typo fix

* resolving toc conflict

* fixed the image link

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Co-authored-by: Sylvain Gugger <35901082+sgugger@users.noreply.github.com>
Co-authored-by: NielsRogge <48327001+NielsRogge@users.noreply.github.com>
Co-authored-by: Sayak Paul <spsayakpaul@gmail.com>