Ensure latest TLS version is used for AWS ElasticSearch Nodes

AWS ElasticSearch Node is not configured to use the latest TLS version. Using the latest version of TLS can help keep data in-transit protected from man-in-the-middle and similar attacks.

To configure the TLS version used for an OpenSearch domain, see the AWS documentation (below). This is done via the CLI and is not available in the Console.

In Terraform -

1. In the aws_elasticsearch_domain resource, set the domain_endpoint_options.tls_security_policy field enabled accordingly.

References:
https://docs.aws.amazon.com/opensearch-service/latest/developerguide/infrastructure-security.html
https://registry.terraform.io/providers/hashicorp/aws/latest/docs/resources/elasticsearch_domain#tls_security_policy