Merge pull request #3424 from tragiclifestories/patch-1

📖 Quote download URL in quickstart docs

Author: k8s-ci-robot

docs/book/src/quick-start.md

@@ -31,7 +31,7 @@ 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)
+curl -L -o kubebuilder "https://go.kubebuilder.io/dl/latest/$(go env GOOS)/$(go env GOARCH)"
 chmod +x kubebuilder && mv kubebuilder /usr/local/bin/
 ```