[en] fix typo in kubeadm-certs.md

Author: Arhell

content/en/docs/tasks/administer-cluster/kubeadm/kubeadm-certs.md

@@ -16,7 +16,7 @@ to kubeadm certificate management.
 
 The Kubernetes project recommends upgrading to the latest patch releases promptly, and
 to ensure that you are running a supported minor release of Kubernetes.
-Following this recommendation helps you to to stay secure.
+Following this recommendation helps you to stay secure.
 
 
 ## {{% heading "prerequisites" %}}