Avoid unnecessary PVCs updates when updating ownerRefs

[pebrc]

Related to #5450

in

cloud-on-k8s/pkg/controller/elasticsearch/driver/pvc_owner.go

Lines 34 to 47 in 9be005d

	for _, pvc := range pvcs.Items {
	pvc := pvc
	switch es.Spec.VolumeClaimDeletePolicyOrDefault() {
	case esv1.DeleteOnScaledownOnlyPolicy:
	k8s.RemoveOwner(&pvc, &es)
	case esv1.DeleteOnScaledownAndClusterDeletionPolicy:
	if err := controllerutil.SetOwnerReference(&es, &pvc, scheme.Scheme); err != nil {
	return fmt.Errorf("while setting owner during owner ref reconciliation: %w", err)
	}
	}
	if err := c.Update(context.Background(), &pvc); err != nil {
	return fmt.Errorf("while updating pvc during owner ref reconciliation: %w", err)
	}
	}

we do not check whether a update of the PVC is actually necessary. We should use a similar approach here as in other cases whereby we compare the current state with the desired state and only issue the update if they differ.

This should significantly reduce the number updates on PVCs the operator does.