Add a recording rule, acm_capacity_effective_cpu_cores, on telemeter server side for ACM subscription usage with two labels, _id and managed_cluster_id.

The rule is built based on the 3 metrics:

• acm_managed_cluster_info
• acm_managed_cluster_worker_cores:sum
• cluster:capacity_effective_cpu_cores
  The metric value is measured in virtual CPU cores. That means physical CPU cores will be normalized to virtual CPU cores (1 physical CPU core = 2 virtual CPU cores).

Here is the logic for the recording rule:

• Self managed OpenShift clusters
    acm_capacity_effective_cpu_cores = 2 * cluster:capacity_effective_cpu_cores
• Managed OpenShift clusters and non-OpenShift clusters
    acm_capacity_effective_cpu_cores = acm_managed_cluster_worker_cores.

Note: If the metric cluster:capacity_effective_cpu_cores is not available for a self managed OpenShift cluster, the value of the metric acm_capacity_effective_cpu_cores will fall back to the metric acm_managed_cluster_worker_cores:sum.

See the DDR for more details: https://docs.google.com/document/d/1WbQyaY3C6MxfsebJrV_glX8YvqqzS5fwt3z8Z8SQ0VY/edit?usp=sharing