I'm trying to use this in an ECS Task, and I'm getting the error "Unable to get IAM security credentials from EC2 Instance Metadata Service." I have set up policies on my ECS Task role to provide access to the specific Secrets I am trying to access, as well as KMS and Session Manager, according to https://aws.amazon.com/premiumsupport/knowledge-center/ecs-data-security-container-task/ and a few other links. Is there anything else that I'm missing that needs to be done to get this to work?