Add .pre-commit-config black settings, blacken SDK

[maxkahan]

Adds black configuration, and also blackens the SDK code.

[codecov-commenter]

Codecov Report

Merging #284 (f0e10a0) into main (29e1d8a) will not change coverage.
The diff coverage is 100.00%.

❗ Current head f0e10a0 differs from pull request most recent head 3839854. Consider uploading reports for the commit 3839854 to get more accurate results

@@           Coverage Diff           @@
##             main     #284   +/-   ##
=======================================
  Coverage   97.33%   97.33%           
=======================================
  Files          25       25           
  Lines        1090     1090           
=======================================
  Hits         1061     1061           
  Misses         29       29           

Files Changed	Coverage Δ
src/vonage/verify.py	100.00% <ø> (ø)
src/vonage/account.py	100.00% <100.00%> (ø)
src/vonage/application.py	100.00% <100.00%> (ø)
src/vonage/client.py	94.24% <100.00%> (ø)
src/vonage/ncco_builder/ncco.py	97.67% <100.00%> (ø)
src/vonage/ncco_builder/pay_prompts.py	100.00% <100.00%> (ø)
src/vonage/number_insight.py	100.00% <100.00%> (ø)
src/vonage/number_management.py	100.00% <100.00%> (ø)
src/vonage/redact.py	100.00% <100.00%> (ø)
src/vonage/short_codes.py	100.00% <100.00%> (ø)
... and 3 more

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