feat(CORS): set allow private network header

[zodecky]

Summary of Changes

Allow private networks as an option in CORS

Related Issues

#2381

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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 100.00%. Comparing base (ab2ce4c) to head (dac0d17).

Additional details and impacted files

@@            Coverage Diff            @@
##            master     #2383   +/-   ##
=========================================
  Coverage   100.00%   100.00%           
=========================================
  Files           64        64           
  Lines         7726      7726           
  Branches      1071      1071           
=========================================
  Hits          7726      7726           

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[vytas7]

Something looks wrong... 😕
Have you changed line endings, or why does the whole file look as changed? Aha, you added middleware.py as a top-level file... Please make changes to falcon/middleware.py instead.

Moreover, before merging, we'll need to add tests covering the new code, and a Towncrier newsfragment.

[zodecky]

Ok! Thank you! I Will change that!