Corrects broken link to GitHub file (#1443)

Noted in internal discussion that the existing link resulted in a 404.
New link resolves.

Author: djwfyi

source/operations/monitoring/grafana.rst

@@ -91,7 +91,7 @@ MinIO Replication Metrics Dashboard
 
 Visualize MinIO bucket metrics with the official MinIO Grafana dashboard for replication available on the `Grafana dashboard portal <https://grafana.com/grafana/dashboards/15305-minio-replication-dashboard/>`__.
 
-Cluster replication metrics can be viewed in the Grafana dashboard using the `cluster replication JSON file on GitHub <https://raw.githubusercontent.com/minio/minio/master/docs/metrics/prometheus/grafana/replication/minio-replication.json>`__.
+Cluster replication metrics can be viewed in the Grafana dashboard using the `cluster replication JSON file on GitHub <https://raw.githubusercontent.com/minio/minio/master/docs/metrics/prometheus/grafana/replication/minio-replication-cluster.json>`__.
 
 .. image:: /images/grafana-replication.png
    :width: 600px