Ensure Elastic Block Store (EBS) volumes are encrypted through AWS Config

AWS Config does not encrypt volumes by default. Encryption will help protect data integrity and confidentiality.

In AWS Console -

1. Sign in to AWS Console and go to the EC2 dashboard.
2. In the navigation panel, under AWS Config, click Rules.
3. Select the AWS Config rule you want to edit in the Edit rule column.
4. On the Config rule page select source identifier as 'ENCRYPTED_VOLUMES'.

In Terraform -

1. In the aws_config_config_rule resource, set the source.source_identifier field to ENCRYPTED_VOLUMES.

References:
https://docs.aws.amazon.com/config/latest/developerguide/WhatIsConfig.html
https://registry.terraform.io/providers/hashicorp/aws/latest/docs/resources/config_config_rule