Use same default config from CLI and API.

[regseb]

Fixes #5845

• Create an object containing the default values.
• Use this object in the CLI options.
• Use this object in the Linter instantiation (in case addons-linter is used by the API).

[codecov[bot]]

Codecov Report

:white_check_mark: All modified and coverable lines are covered by tests. :white_check_mark: Project coverage is 98.79%. Comparing base (51af13f) to head (624e2fb).

Additional details and impacted files

@@           Coverage Diff           @@
##           master    #5863   +/-   ##
=======================================
  Coverage   98.78%   98.79%           
=======================================
  Files          51       51           
  Lines        2892     2893    +1     
  Branches      888      888           
=======================================
+ Hits         2857     2858    +1     
  Misses         35       35           

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