Ensure tracing is enabled for AWS Lambda Functions

Lambda tracing if not enabled can have an impact the integrity and incident response.

In AWS Console -

1. Sign in to AWS Console and go to the Functions page on the Lambda console.
2. Select a function.
3. Select Configuration and then choose Monitoring tools.
4. Select Edit.
5. Under X-Ray, enable Active tracing.
6. Click Save.

In Terraform -

1. In the aws_lambda_function resource, set the tracing_config.mode field to Active.

References:
https://docs.aws.amazon.com/lambda/latest/dg/services-xray.html
https://registry.terraform.io/providers/hashicorp/aws/latest/docs/resources/lambda_function#tracing_config