k8s-operator/dnsrecords: fix dnsRR dropping reconcile events on lock err (#19968)

On optimistic lock error, requeue the event after a short duration.

Resolves a case where a failure to acquire an optimistic lock on the
dnsrecords configmap will cause the operator to drop a reconcile event
and leave the configmap in an undesirable state.

Updates tailscale/tailscale#19946

Signed-off-by: Alex Freestone <freestone.alex@gmail.com>

cmd/k8s-operator/dnsrecords.go

@@ -107,6 +107,7 @@ func (dnsRR *dnsRecordsReconciler) Reconcile(ctx context.Context, req reconcile.
 	if err := dnsRR.maybeProvision(ctx, proxySvc, logger); err != nil {
 		if strings.Contains(err.Error(), optimisticLockErrorMsg) {
 			logger.Infof("optimistic lock error, retrying: %s", err)
+			return reconcile.Result{RequeueAfter: shortRequeue}, nil
 		} else {
 			return reconcile.Result{}, err
 		}