Resolve GWG-37 "Mimir setup"

Closes GWG-37

grafana-central/datasources/prometheus.yaml

@@ -12,7 +12,7 @@ datasources:
     # <string> custom UID which can be used to reference this datasource in other parts of the configuration, if not specified will be generated automatically
     uid: prometheus
     # <string> url
-    url: http://localhost:9090
+    url: http://localhost:9009/prometheus
     # <string> Deprecated, use secureJsonData.password
     password:
     # <string> database user, if used