refactor(event-handler): remove kwargs from AppSync exception constructor

[T90REAL]

Issue number: closes #7693

Summary

Remove **kwargs from the signature to avoid confusing customers.

Changes

Delete **kwargs from argument and doc.

User experience

User will not be confused by the signatures.

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[boring-cyborg]

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[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 96.52%. Comparing base (f77c259) to head (016608b).
⚠️ Report is 2 commits behind head on develop.

Additional details and impacted files

@@           Coverage Diff            @@
##           develop    #7699   +/-   ##
========================================
  Coverage    96.52%   96.52%           
========================================
  Files          275      275           
  Lines        13117    13117           
  Branches       986      986           
========================================
  Hits         12661    12661           
  Misses         353      353           
  Partials       103      103           

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[dreamorosi]

Hi @T90REAL, thank you for sending the PR.

Well done 🚢 !

[boring-cyborg]

Awesome work, congrats on your first merged pull request and thank you for helping improve everyone's experience!