(docs/quick-start): Fix generated controller file path

Signed-off-by: Shinebayar Gansukh <3091558+shinebayar-g@users.noreply.github.com>

Author: shinebayar-g

docs/book/src/quick-start.md

@@ -78,7 +78,7 @@ kubebuilder create api --group webapp --version v1 --kind Guestbook
 <h1>Press Options</h1>
 
 If you press `y` for Create Resource [y/n] and for Create Controller [y/n] then this will create the files `api/v1/guestbook_types.go` where the API is defined
-and the `internal/controllers/guestbook_controller.go` where the reconciliation business logic is implemented for this Kind(CRD).
+and the `internal/controller/guestbook_controller.go` where the reconciliation business logic is implemented for this Kind(CRD).
 
 </aside>