Add StorageObjectInUseProtection to the default enabled admission plugins (#16261)

Author: houjun41544

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

@@ -89,10 +89,10 @@ To see which admission plugins are enabled:
 kube-apiserver -h | grep enable-admission-plugins
 ```
 
-In 1.14, they are:
+In 1.15, they are:
 
 ```shell
-NamespaceLifecycle, LimitRanger, ServiceAccount, TaintNodesByCondition, Priority, DefaultTolerationSeconds, DefaultStorageClass, PersistentVolumeClaimResize, MutatingAdmissionWebhook, ValidatingAdmissionWebhook, ResourceQuota
+NamespaceLifecycle, LimitRanger, ServiceAccount, TaintNodesByCondition, Priority, DefaultTolerationSeconds, DefaultStorageClass, PersistentVolumeClaimResize, MutatingAdmissionWebhook, ValidatingAdmissionWebhook, ResourceQuota, StorageObjectInUseProtection
 ```
 
 ## What does each admission controller do?