Summary

This PR introduces a new GitHub Actions workflow that tests kURL deployments on Compatibility Matrix (CMX) clusters. It creates a real kURL cluster via the replicated CLI, validates provisioning, and ensures the cluster is functional before cleanup.

Changes

• Added .github/workflows/test-cmx-clusters.yaml
• Workflow runs on workflow_dispatch and daily at 06:00 UTC via cron schedule
• Installs replicated CLI and creates a kURL CMX cluster (r1.large instance type)
• Validates cluster health by:
  • Retrieving kubeconfig and listing nodes, namespaces, pods, and services
  • Verifying the kurl namespace exists
  • Waiting for all nodes to be Ready
  • Testing DNS resolution within the cluster
• Implements automatic cleanup with always() condition to remove CMX clusters even if tests fail
• Restricted to run only on the replicatedhq organization

UAT

1. Go to the Actions tab in the repository
2. Select test-cmx-clusters workflow
3. Click Run workflow and trigger it manually
4. Verify that:
   • The CMX cluster is created successfully
   • Validation steps pass (nodes ready, DNS works, kurl namespace exists)
   • Cluster is removed automatically after completion (check the cleanup step)