(fleet/cnpg-cluster) bump cnpgsphere 16.8 on manke

Author: cbarria

fleet/lib/cnpg-cluster/overlays/manke/cluster-cnpg-cluster.yaml

@@ -5,7 +5,7 @@ kind: Cluster
 metadata:
   name: cnpg-cluster
 spec:
-  imageName: docker.io/lsstit/cnpgsphere:14.5
+  imageName: docker.io/lsstit/cnpgsphere:16.8
   imagePullPolicy: IfNotPresent
 
   instances: 3