Allow bring your own logger to Feature Flags

[gwlester]

Is your feature request related to a problem? Please describe.

Users would like to use a customized logger.

Describe the solution you'd like

Add the ability to pass a logger instance, defaulted to None into the object creation of the following classes:

• AppConfigStore
• FeatureFlags
• SchemaValidator
• FeaturesValidator
• RulesValidator
• ConditionsValidator

The init method would create a logger instance if None was passed in.

Describe alternatives you've considered

Additional context

[gwlester]

I attempted to push an implementation of this up to then create a push request, but it seems I'm not authorized.

Can I get added to the contributors list?

[to-mc]

@gwlester you'll need to fork this repository then push your changes to a branch in your own fork. You can then create a PR from your own fork against this repo. If you're having issues, come ping us in #lambda-powertools on the AWS Developer Slack (invite if you need one) and we'll help.

[heitorlessa]

Now available as part of 1.21.0 :) https://github.com/awslabs/aws-lambda-powertools-python/releases/tag/v1.21.0