recommended admission controllers are enabled by default (#14784)

Since the recommended ones are already enabled by default, they do not need to be explicitly specified with `--enable-admission-plugins`

content/en/docs/reference/access-authn-authz/admission-controllers.md

@@ -624,16 +624,12 @@ versions 1.9 and later).
 
 Yes.
 
-For Kubernetes version 1.10 and later, we recommend running the following set of admission controllers using the `--enable-admission-plugins` flag (**order doesn't matter**).
+For Kubernetes version 1.10 and later, the recommended admission controllers are enabled by default, so you do not need to explicitly specify them. You can enable additional admission controllers beyond the default set using the `--enable-admission-plugins` flag (**order doesn't matter**).
 
 {{< note >}}
 `--admission-control` was deprecated in 1.10 and replaced with `--enable-admission-plugins`.
 {{< /note >}}
 
-```shell
---enable-admission-plugins=NamespaceLifecycle,LimitRanger,ServiceAccount,DefaultStorageClass,DefaultTolerationSeconds,MutatingAdmissionWebhook,ValidatingAdmissionWebhook,Priority,ResourceQuota
-```
-
 For Kubernetes 1.9 and earlier, we recommend running the following set of admission controllers using the `--admission-control` flag (**order matters**).
 
 * v1.9