Downgrade grafana to fix beegfs quota plot as suggested here:...

Downgrade grafana to fix beegfs quota plot as suggested here: https://community.grafana.com/t/no-graphable-fields-after-upgrade-to-8-0-3/51897

roles/grafana_monitoring/tasks/main.yml

@@ -66,7 +66,7 @@
 - name: Launch grafana monitoring
   docker_container:
     name: "edd_grafana"
-    image: grafana/grafana:8.1.2
+    image: grafana/grafana:8.0.2
     detach: yes
     state: started            # ensure that is running
     network_mode: bridge