deletePairConfigMaps can return an error if a listed ConfigMap is already gone

[ChaoHuang2018]

Hi HyperShift maintainers,

While looking at the dedicated request-serving cleanup path, I noticed that deletePairConfigMaps lists matching ConfigMaps and then deletes each one, but it appears to return any Delete error directly.

The helper lists pair ConfigMaps in the placeholder namespace:

dedicated_request_serving_nodes.go:422-L428

It then deletes the ConfigMaps whose data points back to the HostedCluster:

dedicated_request_serving_nodes.go:429-L433

This cleanup runs during HostedCluster deletion before the scheduler finalizer is removed:

dedicated_request_serving_nodes.go:529-L545

The race I am wondering about is:

reconcile A lists a pair ConfigMap for the HostedCluster
reconcile B or another cleanup path deletes that ConfigMap
reconcile A calls Delete on the stale listed object
Delete returns NotFound
handleDeletion returns the error before removing the scheduler finalizer

For this kind of list-then-delete cleanup, NotFound after the list is usually an idempotent success: the desired cleanup state has already been reached. Returning the error can make the deletion path fail for a transient stale-list race and delay finalizer removal until a later reconcile.

Would it make sense to ignore apierrors.IsNotFound(err) around this r.Delete call, similar to other Kubernetes cleanup paths that treat an already-deleted object as success?