take some action immediately after upgrading. In multi-tenant clusters where not all users are trusted, you are advised to create appropriate quotas for two default priority classes, system-cluster-critical and system-node-critical, which are added to clusters by default. `ResourceQuota` should be created to limit users from creating Pods at these priorities if not all users of your cluster are trusted. We do not advise disabling this feature because critical system Pods rely on the scheduler preemption...