[CONTINT-5389] Collect kubelet_containers_per_pod_count in the kubelet check (DataDog#24600)

* Added kubelet.containers_per_pod to metadata.csv

* Changed metric descriptions in metadata.csv

Author: sehgal23

kubelet/metadata.csv

@@ -53,6 +53,8 @@ kubernetes.kubelet.pleg.relist_duration.count,gauge,,,,The count of relisting po
 kubernetes.kubelet.pleg.relist_duration.sum,gauge,,second,,The sum of duration in seconds for relisting pods in PLEG,0,kubernetes,k8s.pleg.relist_dur,
 kubernetes.kubelet.pleg.relist_interval.count,gauge,,second,,The count of relisting pods in PLEG,0,kubernetes,k8s.pleg.relist_interv,
 kubernetes.kubelet.pleg.relist_interval.sum,gauge,,,,The sum of interval in seconds between relisting in PLEG,0,kubernetes,k8s.pleg.relist_interv,
+kubernetes.kubelet.containers_per_pod.count,gauge,,,,The count of the number of containers per pod,0,kubernetes,k8s.containers_per_pod,
+kubernetes.kubelet.containers_per_pod.sum,gauge,,,,The cumulative sum of the number of containers per pod,0,kubernetes,k8s.containers_per_pod,
 kubernetes.kubelet.runtime.operations,count,,operation,,The number of runtime operations,0,kubernetes,k8s.runtime.ops,
 kubernetes.kubelet.runtime.errors,gauge,,operation,,Cumulative number of runtime operations errors,-1,kubernetes,k8s.runtime.err,
 kubernetes.kubelet.runtime.operations.duration.sum,gauge,,operation,,The sum of duration of operations,0,kubernetes,k8s.runtime.duration,