Logger to support arbitrary key=value style arguments in log statements

[heitorlessa]

Original author: @CeeBeeCee

Runtime: Python

Is your feature request related to a problem? Please describe

As per discussion originally posted on Python repo, this feature request is related to Logger being able to use key value arguments in log statements e.g. logger.info("my message", my_key="value", request_id="123d023f0-alk322f").

Describe the solution you'd like

I'd like to add additional keys on a per log statement basis by passing an arbitrary number of key=value arguments to .info, .warn, etc..

Describe alternatives you've considered

1. Use extra={} parameter as supported by Logger and in standard logging library
2. Continue to use structlog

If you provide guidance, is this something you'd like to contribute?

Additional context

[heitorlessa]

cc @pankajagrawal16 @saragerion @cakepietoast as I added all_runtimes label

[saragerion]

This is already supported by the TypeScript powertool 🥳
https://github.com/awslabs/aws-lambda-powertools-typescript/blob/main/packages/logger/tests/unit/Logger.test.ts#L286