Ensure already migrated CRBs are not duplicated in the gardeneraccess MR (gardener#13310)

Co-authored-by: vpnachev <vladimir.nachev@sap.com>
(cherry picked from commit 9002f97)

Author: 2 people

cmd/gardenlet/app/migration.go

@@ -117,6 +117,10 @@ func migrateAdminViewerKubeconfigClusterRoleBindings(ctx context.Context, log lo
 				return fmt.Errorf("failed to get objects for ManagedResource %q: %w", gardenerAccessKey, err)
 			}
 
+			gardenerAccessObjects = slices.DeleteFunc(gardenerAccessObjects, func(obj client.Object) bool {
+				return slices.Contains(crbs, obj.GetName())
+			})
+
 			gardenerAccessObjects = append(gardenerAccessObjects, gardeneraccess.ShootAccessClusterRoleBindings()...)
 			gardenerAccessRegistry := managedresources.NewRegistry(kubernetes.ShootScheme, kubernetes.ShootCodec, kubernetes.ShootSerializer)
 			gardenerAccessResources, err := gardenerAccessRegistry.AddAllAndSerialize(gardenerAccessObjects...)