Add support for configuring EFA receiver on EC2 via JSON

[mitali-salvi]

Description of the issue

Add support for configuring the awsefareceiver via the CWA JSON configuration. Customers will be able to configure EFA (Elastic Fabric Adapter) metrics collection under metrics.metrics_collected.efa.

EFA is a distinct hardware type (Elastic Fabric Adapter) that exposes 22 cumulative monotonic sum
metrics via /sys/class/infiniband/ sysfs.

Collect all 22 EFA metrics with defaults:

json
{
  "metrics": {
    "metrics_collected": {
      "efa": {}
    }
  }
}

Collect specific metrics with a custom interval and selected metrics:

json
{
  "metrics": {
    "metrics_collected": {
      "efa": {
        "measurement": ["efa_tx_bytes", "efa_rx_bytes", "efa_rdma_read_bytes"],
        "metrics_collection_interval": 30
      }
    }
  }
}

License

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Tests

• Unit tests: 9 test cases all passing
• Manual: deployed CWA to EC2 instance with EFA devices, generated traffic between two EFA-
  enabled instances, confirmed agent starts and collects metrics

Requirements

Before commiting your code, please do the following steps.

1. Run make fmt and make fmt-sh
2. Run make lint

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Integration Tests

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