Config: AWS maintained required tags rule not recording Lambda Functions

In required tags documentation it doesn't list out Lambda resource. I would suggest going through Custom Config Rdk as shown in the below documentation and deploying it in your region.

1. https://github.com/awslabs/aws-config-rules/blob/master/python/lambda_require_tags_with_valid_values.py
2. Required tags documentation where lambda is not included - https://docs.aws.amazon.com/config/latest/developerguide/required-tags.html