mimir-microservices-mode: add prometheus datasource (#10354)

* mimir-microservices-mode: add prometheus datasource

this is useful to use as a datasource when the Mimir cluster has an outage

Signed-off-by: Dimitar Dimitrov <dimitar.dimitrov@grafana.com>

* Remove prometheusTypeMimir

Signed-off-by: Dimitar Dimitrov <dimitar.dimitrov@grafana.com>

---------

Signed-off-by: Dimitar Dimitrov <dimitar.dimitrov@grafana.com>

development/mimir-microservices-mode/config/datasources.yaml

@@ -13,6 +13,13 @@ datasources:
     - name: traceID
       datasourceUid: jaeger
 
+- name: Prometheus
+  type: prometheus
+  access: proxy
+  uid: prometheus
+  orgID: 1
+  url: http://prometheus:9090
+
 - name: Mimir (query results caching disabled)
   type: prometheus
   access: proxy