What does this PR do?

• Adds 3 env vars to the cluster Agent:
  • AGENT_DAEMONSET: name of the node Agent ds
  • CLUSTER_AGENT_DEPLOYMENT: name of the DCA deployment
  • DATADOGAGENT_CR_NAME: name of the DatadogAgent custom resource
• Adds RBAC allowing the DCA to get the DatadogAgent custom resource from its namespace

Motivation

Similar to DataDog/helm-charts#965, we need to inject a few variables/give some permissions to be able to collect the Agent deployment files while creating a flare to help with troubleshooting.

Additional Notes

The flare feature depending on these variables is available at: DataDog/datadog-agent#30372

Minimum Agent Versions

Are there minimum versions of the Datadog Agent and/or Cluster Agent required?

• Agent: vX.Y.Z
• Cluster Agent: vX.Y.Z

Describe your test plan

• Deploy the operator
• Deploy a DatadogAgent with cluster Agent enabled (default):

apiVersion: datadoghq.com/v2alpha1
kind: DatadogAgent
metadata:
  name: foo

• Assert on DCA:
  • AGENT_DAEMONSET: foo-agent, value of kubectl get ds
  • CLUSTER_AGENT_DEPLOYMENT: foo-cluster-agent, value of kubectl get deploy
  • DATADOGAGENT_CR_NAME: foo, value of kubectl get dd
• Add overrides:

apiVersion: datadoghq.com/v2alpha1
kind: DatadogAgent
metadata:
  name: foo
override:
  nodeAgent:
    name: "x"
  clusterAgent:
    name: "y"

• Assert on DCA:
  • AGENT_DAEMONSET: x, value of kubectl get ds
  • CLUSTER_AGENT_DEPLOYMENT: y, value of kubectl get deploy
  • DATADOGAGENT_CR_NAME: foo, value of kubectl get dd

Checklist

• PR has at least one valid label: bug, enhancement, refactoring, documentation, tooling, and/or dependencies
• PR has a milestone or the qa/skip-qa label