Enable Automatic Image Pruning in OpenShift Container Platform 4

Issue

• An alert fires with the following error message, usually after upgrading to OpenShift 4.4:

"Automatic image pruning is not enabled. Regular pruning of images no longer referenced by ImageStreams is strongly recommended to ensure your cluster remains healthy. To remove this warning, install the image pruner by creating an imagepruner.imageregistry.operator.openshift.io resource with the name cluster. Ensure that the suspend field is set to false."

• The API object is documented here.