Update grafana/grafana Docker tag to v9.1.6 (#1261)

Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

Author: renovate[bot]

docker-compose.yaml

@@ -107,7 +107,7 @@ services:
         constraints:
           - "node.role==manager"
   grafana:
-    image: grafana/grafana:9.1.5
+    image: grafana/grafana:9.1.6
     ports:
       - "9100:3000"
     volumes: