feat(event-handler): add error handling functionality to BaseRouter

[svozza]

Summary

This PR adds error handling logic to the BaaseRouter class

Changes

BaseRouter

• Added specific methods to register NotFound and MethodNotAllowed handlers
• Added error handler methods, these take an error and check the registry to see if there is a registered handler. If not it has a fallback to a default error handler that will return a 500 error
• Unit tests that test the error registry logic is handled correctly

Issue number: #4141

Final part of the error handling piece is to add support for decorators. I have left that till last because I wanted the logic to be easily reviewable before we added the method overloads and bolierplate to support them.

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[powertools-for-aws-oss-automation]

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[dreamorosi]

Thanks for this PR - left a few comments

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
29.5% Duplication on New Code

See analysis details on SonarQube Cloud