Fix noisy reconcile errors (#275)

Certain errors are better ignored to instead rely on the child resource
to trigger a new reconcile.

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## Summary by CodeRabbit

## Release Notes

* **Bug Fixes**
* Enhanced error handling in group resolution to prevent silent failures
and ensure proper error notification
* Improved system resilience by gracefully handling missing or
unavailable Kubernetes resources without triggering reconciliation
failures
* Optimized setup key processing workflow to enhance overall system
robustness and reliability

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internal/controller/group_controller.go

@@ -50,6 +50,9 @@ func (r *GroupReconciler) Reconcile(ctx context.Context, req ctrl.Request) (ctrl
 	groupID, err := func() (string, error) {
 		if group.Status.GroupID != "" {
 			groupResp, err := r.Netbird.Groups.Get(ctx, group.Status.GroupID)
+			if err != nil && !netbird.IsNotFound(err) {
+				return "", err
+			}
 			if err == nil {
 				peers := []string{}
 				for _, peer := range groupResp.Peers {