Support EBS attached ECS tasks

[thaim]

The script check-ecs-exec.sh currently encounters a subnet ID parsing error when used with ECS tasks that have EBS volumes attached. The error arises because the script incorrectly assumes that the attachments array includes only network interfaces.

An error occurred (InvalidSubnetID.NotFound) when calling the DescribeSubnets operation: The subnet ID '' does not exist

The check-ecs-exec.sh script is designed to parse only ElasticNetworkInterface from the attachments array returned by the aws ecs describe-tasks command. If an ECS task has an EBS volume attached, the array might also contain AmazonElasticBlockStorage objects, which can lead to incorrect parsing if these are listed before any network interfaces.

Update the parsing logic within check-ecs-exec.sh to accurately handle multiple types of attachments, focusing specifically on ElasticNetworkInterface objects for subnet ID extraction. This ensures the script disregards any AmazonElasticBlockStorage objects or other non-network-related attachments that could interfere with the correct parsing process.

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