The API for setting resource isn't convenient

[simonpasquier]

.spec.resources's description says "Define resources requests and limits for Monitoring Stack Pods" which is misleading because the resources requests are only applied to the Prometheus resource and we have no way to define requests for Alertmanager.

Instead of

spec:
  resources:
    requests:
      cpu: 200m
      memory: 1Gi

The API should probably look like

spec:
  prometheusConfig:
    resources:
      requests:
        cpu: 200m
        memory: 1Gi
  alertmanagerConfig:
    resources:
      requests:
        cpu: 200m
        memory: 1Gi

I didn't create a ticket in JIRA but I can do later.