text: Title: Misnamed feature gate in API server help
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  #### What happened:
  https://kubernetes.io/docs/reference/generated/kubernetes-api/v1.21/#list-deployment-v1-apps (which is generated automatically) mentions a feature gate named `WatchBookmarks`. This is not the correct name; that feature gate is / was `WatchBookmark`. Also, the feature has graduated.
  
  So what happened was I saw an incorrect feature gate name.
  
  #### What you expected to happen:
  The generated docs don't mention `WatchBookmark` _or_ `WatchBookmarks` 
  
  
  ie, I think the fix is to remove
  ```go
  	// If the feature gate WatchBookmarks is not enabled in apiserver,
  	// this field is ignored.
  ```
  
  #### How to reproduce it (as minimally and precisely as possible):
  - generate the documentation
  - read the documentation
  
  or, short cut, go and look at https://github.com/kubernetes/apimachinery/blob/8daf28983e6ecf28bd8271925ee135c1179ad13a/pkg/apis/meta/v1/types.go#L360
  
  #### Anything else we need to know?:
  
  
  #### Environment:
  - Kubernetes version (use `kubectl version`): v1.21
  - Cloud provider or hardware configuration: n/a
  - OS (e.g: `cat /etc/os-release`): n/a
  - Kernel (e.g. `uname -a`): n/a
  - Install tools: n/a
  - Network plugin and version (if this is a network-related bug):
  - Others: 
  
  /kind bug
  /sig api-machinery
  /priority backlog
  (IMO)
  