Modify session to use HTTPAdapter and handle retries

[fronzbot]

Description:

Adds automatic retry on failures and throttling

Checklist:

• Local tests with tox run successfully PR cannot be meged unless tests pass
• Changes tested locally to ensure platform still works as intended
• Tests added to verify new code works

[codecov]

Codecov Report

Merging #324 into dev will increase coverage by 0.14%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##              dev     #324      +/-   ##
==========================================
+ Coverage   82.75%   82.90%   +0.14%     
==========================================
  Files           8        8              
  Lines         928      936       +8     
==========================================
+ Hits          768      776       +8     
  Misses        160      160              

Flag	Coverage Δ
#unittests	82.90% <100.00%> (+0.14%)	⬆️

Impacted Files	Coverage Δ
blinkpy/auth.py	95.10% <100.00%> (+0.29%)	⬆️

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