feat: Fix prometheus documentation link

Author: ADubhlaoich

content/ngf/overview/nginx-plus.md

@@ -10,7 +10,7 @@ NGINX Gateway Fabric can use NGINX Open Source or NGINX Plus as its data plane.
 
 ## Benefits of NGINX Plus
 
-- **Robust metrics**: A plethora of [additional Prometheus metrics](https://github.com/nginx/nginx-prometheus-exporter#metrics-for-nginx-plus) are available.
+- **Robust metrics**: A plethora of [additional Prometheus metrics]( "/ngf/monitoring/prometheus.md" ) are available.
 - **Live activity monitoring**: The [NGINX Plus dashboard]({{< ref "/ngf/monitoring/dashboard.md" >}}) shows real-time metrics and information about your server infrastructure.
 - **Dynamic upstream configuration**: NGINX Plus can dynamically reconfigure upstream servers when applications in Kubernetes scale up and down, preventing the need for an NGINX reload.
 - **Support**: With an NGINX Plus license, you can take advantage of full [support](https://my.f5.com/manage/s/article/K000140156/) from NGINX, Inc.