Update QA to new inputs and datamodule

[ethanwharris]

What does this PR do?

Fixes #964
Fixes #955

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[tchaton]

Looks dope !

[codecov]

Codecov Report

Merging #1045 (123c6fd) into master (d1e3c09) will increase coverage by 0.14%.
The diff coverage is 96.13%.

@@            Coverage Diff             @@
##           master    #1045      +/-   ##
==========================================
+ Coverage   86.66%   86.80%   +0.14%     
==========================================
  Files         272      275       +3     
  Lines       13885    13797      -88     
==========================================
- Hits        12033    11977      -56     
+ Misses       1852     1820      -32     

Flag	Coverage Δ
unittests	86.80% <96.13%> (+0.14%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
flash/text/question_answering/cli.py	100.00% <ø> (ø)
flash/text/question_answering/output_transform.py	63.63% <63.63%> (ø)
flash/text/question_answering/data.py	93.10% <92.30%> (+6.26%)	⬆️
flash/text/question_answering/input.py	98.17% <98.17%> (ø)
flash/core/integrations/transformers/transforms.py	100.00% <100.00%> (ø)
flash/text/question_answering/input_transform.py	100.00% <100.00%> (ø)
flash/text/question_answering/model.py	91.15% <100.00%> (+0.12%)	⬆️
flash/core/utilities/stages.py	73.91% <0.00%> (-4.35%)	⬇️

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