Title: RH-OBS resources are not accessed unless the full API group is specified

Description: It is not possible to list/edit/access Red Hat OpenShift Observability (RH-OBS) custom resources using the standard oc get <resource_kind> command. The command fails unless the resource's full API group (<resource>.<api_group>) is provided.

Example: 

Below commands do not list the rhobs resources:

$ oc get alertmanagerconfig
$ oc get alertmanager
$ oc get monitoringstack
$ oc get prometheusrule

But below command does:

$ oc get alertmanagerconfig.monitoring.rhobs
$ oc get alertmanager.monitoring.rhobs
$ oc get monitoringstack.monitoring.rhobs
$ oc get prometheusrule.monitoring.rhobs

Expected behaviour:

Below commands should list all the resources irrespective of the api groups:

$ oc get alertmanagerconfig
$ oc get alertmanager
$ oc get monitoringstack
$ oc get prometheusrule