Update Speech Recognition example (with learning_rate)

[krshrimali]

What does this PR do?

Addresses #1112 to add learning_rate to the SpeechRecognition constructor.

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[codecov]

Codecov Report

Merging #1272 (6ee6570) into master (3c74081) will increase coverage by 8.50%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master    #1272      +/-   ##
==========================================
+ Coverage   81.16%   89.66%   +8.50%     
==========================================
  Files         284      284              
  Lines       12745    12745              
==========================================
+ Hits        10344    11428    +1084     
+ Misses       2401     1317    -1084     

Flag	Coverage Δ
unittests	89.66% <ø> (+8.50%)	⬆️

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

Impacted Files	Coverage Δ
flash/core/data/io/input_transform.py	70.95% <0.00%> (+0.25%)	⬆️
flash/core/data/data_module.py	94.16% <0.00%> (+0.36%)	⬆️
flash/text/question_answering/model.py	85.13% <0.00%> (+0.67%)	⬆️
flash/core/data/utilities/classification.py	98.24% <0.00%> (+1.16%)	⬆️
flash/core/data/properties.py	90.62% <0.00%> (+1.56%)	⬆️
flash/core/data/transforms.py	96.49% <0.00%> (+1.75%)	⬆️
flash/image/segmentation/data.py	100.00% <0.00%> (+2.00%)	⬆️
flash/image/classification/data.py	97.87% <0.00%> (+2.83%)	⬆️
flash/core/adapter.py	97.14% <0.00%> (+2.85%)	⬆️
flash/image/classification/input_transform.py	84.37% <0.00%> (+3.12%)	⬆️
... and 47 more

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[ethanwharris]

LGTM 😃

[ethanwharris]

Closing in favour of #1275