🔧 [#69] Add Pyright configuration

[OlhaZahoruiko]

Closes #69

[codecov-commenter]

Codecov Report

❌ Patch coverage is 85.00000% with 6 lines in your changes missing coverage. Please review.
✅ Project coverage is 83.43%. Comparing base (5d7d19a) to head (fb24909).

Files with missing lines	Patch %	Lines
notifications_api_common/viewsets.py	50.00%	5 Missing ⚠️
notifications_api_common/kanalen.py	88.88%	1 Missing ⚠️

Additional details and impacted files

@@                       Coverage Diff                        @@
##           feature/68-migrate-setup.cfg      #71      +/-   ##
================================================================
+ Coverage                         83.38%   83.43%   +0.05%     
================================================================
  Files                                22       22              
  Lines                               614      628      +14     
  Branches                             45       45              
================================================================
+ Hits                                512      524      +12     
- Misses                               80       82       +2     
  Partials                             22       22              

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[stevenbal]

Could you also run make sure the tests are run using tox and remove this job (similar to what I did in maykinmedia/open-api-framework#210)?