[BUG] Detector heartbeat on ECS Cluster

[gbloquel]

What is the module?
integration_aws-ecs-cluster

What is the detector?
heartbeat

Describe the bug
The heartbeat detector uses the metrics CPUReservation
In the AWS documentation we can see that this metrics is only available for ECS cluster with EC2 instances.
In my case I use AWS Fargate with ECS and not with EC2 instances.

To Reproduce
Steps to reproduce the behavior:

1. Instanciate a cluster ECS with Fargate
2. Use this detector
3. We can see no datas in heartbeat detectors

Expected behavior
To have datas on this detector.

[gbloquel]

Maybe the problem is documentary and explain that all detectors are only usable on ECS Cluster with EC2 instances.

The others detectors cpu_utilization and memory_utilization retrieves no datas.
The AWS documentation explains that memory and CPU utilization metrics are only used for tasks using the EC2 launch type when metrics that are filtered by ClusterName without ServiceName