Admission controller should mark pods in non-labeled namespaces

The admission controller allows pods in configured namespaces to be either bypassed entirely, or passed through to YuniKorn but not labeled for processing (useful in the plugin deployment to pass through to the default scheduler). However, if YuniKorn detects an applicationId or Spark spark-app-selector, it will attempt to schedule that Pod via YuniKorn regardless. This may not succeed if there is not a valid queue available which matches placement rules.

To prevent this, the admission controller should annotate pods which are in non-labeled namespaces to mark them as ignored by yunikorn, and the scheduler should honor this annotation. This will ensure that a namespace is either processed completely by YuniKorn, or not at all.