[website] servicemonitorCRD is need before install prometheus.yaml (#…

…2259)

* servicemonitorCustomResourceDefinition is need before install prometheus.yaml

Signed-off-by: lowang-bh <lhui_wang@163.com>

* Update site/content/en/docs/installation/_index.md

Co-authored-by: Yuki Iwai <yuki.iwai.tz@gmail.com>
Signed-off-by: lowang-bh <lhui_wang@163.com>

---------

Signed-off-by: lowang-bh <lhui_wang@163.com>
Co-authored-by: lowang-bh <lhui_wang@163.com>
Co-authored-by: Yuki Iwai <yuki.iwai.tz@gmail.com>

site/content/en/docs/installation/_index.md

@@ -64,6 +64,10 @@ kubectl apply --server-side -f https://github.com/kubernetes-sigs/kueue/releases
 To allow [prometheus-operator](https://github.com/prometheus-operator/prometheus-operator)
 to scrape metrics from kueue components, run the following command:
 
+> **Note**: This feature depends on [servicemonitor CRD](https://github.com/prometheus-operator/kube-prometheus/blob/main/manifests/setup/0servicemonitorCustomResourceDefinition.yaml), please ensure that CRD is installed first.
+> We can follow `https://prometheus-operator.dev/docs/prologue/quick-start/` to install it.
+> 
+
 ```shell
 kubectl apply --server-side -f https://github.com/kubernetes-sigs/kueue/releases/download/$VERSION/prometheus.yaml
 ```