Update quick-start.md

Permission denied to move the executable to /usr/local/bin. Need sudo permissions

docs/book/src/quick-start.md

@@ -32,7 +32,7 @@ Install [kubebuilder](https://sigs.k8s.io/kubebuilder):
 ```bash
 # download kubebuilder and install locally.
 curl -L -o kubebuilder "https://go.kubebuilder.io/dl/latest/$(go env GOOS)/$(go env GOARCH)"
-chmod +x kubebuilder && mv kubebuilder /usr/local/bin/
+chmod +x kubebuilder && sudo mv kubebuilder /usr/local/bin/
 ```
 
 <aside class="note">