Adding a MachinePool and then deleting it persists the node and ec2 instance. After deleting the node and terminating the ec2 instance, the ec2 instance is re-created and the node re-added to the cluster

    4.5.17

    I can sometimes reproduce on my cluster

1. Add a machinepool to an existing cluster from https://console.redhat.com/openshift/ cluster/machinepools tab or rosa cli
2. Wait for the node to be up and running
3. Drain/cordon the node (optional)
4. Delete the machinepool
     

- machine pool is deleted and does not show in the https://console.redhat.com/openshift/
- node(s) is(are) still registered to the cluster (they show in `oc get nodes` and in the console at Compute->Nodes
- aws shows the instance as running.

- machine pool is deleted and does not show on console.redhat.com/openshift/
- node(s) is(are) deleted from the list of nodes in the cluster (`oc get nodes` or console->Admin->Compute->Nodes)
- aws EC2 instance is shown as terminated from the aws console 
 

- If I manually delete the node using `oc delete node` and terminate the aws instance, the aws instance and nodes are recreated
- If I re-create a machine pool and re-delete it, the issue seems to go away