Add note about projects when user is deleted

doc/user/profile/account/delete_account.md

 # Deleting a User Account
+NOTE: **Note:**
+Deleting a user will delete all projects in that user namespace.
+
 - As a user, you can delete your own account by navigating to **Settings** > **Account** and selecting **Delete account**
 - As an admin, you can delete a user account by navigating to the **Admin Area**, selecting the **Users** tab, selecting a user, and clicking on **Delete user**