feature: be able to disable lambda_unhandled_exception_warning_message

[packplusplus]

Issue #, if available:
#139

Description of changes:
Make the appearance of the lambda_unhandled_exception_warning_message optional. It is excessively long, and there are cases (like an api gateway authorizer) where you MUST use an unhandled exception to get information back to a client (See: https://stackoverflow.com/questions/64909861/how-to-return-401-from-aws-lambda-authorizer-without-raising-an-exception).

Target (OCI, Managed Runtime, both):

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[marshaiev-dashdevs]

Will be good it that will be merged