Removed not relevant FAQ item (#7137)

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- [ ] I have increased versions of npm packages if it is necessary

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[cvat-core](https://github.com/opencv/cvat/tree/develop/cvat-core#versioning),

[cvat-data](https://github.com/opencv/cvat/tree/develop/cvat-data#versioning)
and

[cvat-ui](https://github.com/opencv/cvat/tree/develop/cvat-ui#versioning))

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site/content/en/docs/faq.md

@@ -93,11 +93,6 @@ volumes:
  o: bind
 ```
 
-## How to make unassigned tasks not visible to all users
-
-Set [reduce_task_visibility](https://github.com/cvat-ai/cvat/blob/develop/cvat/settings/base.py#L455)
-variable to `True`.
-
 ## Where are uploaded images/videos stored
 
 The uploaded data is stored in the `cvat_data` docker volume: