chore(deps): pin dependencies

Signed-off-by: renovate-sh-app[bot] <219655108+renovate-sh-app[bot]@users.noreply.github.com>

Author: renovate-sh-app[bot]

docker-compose.yaml

@@ -1,14 +1,14 @@
 services:
   grafana:
-    image: 'grafana/grafana-oss'
+    image: 'grafana/grafana-oss@sha256:5dad0df181cb644a14e13617b913b261a54f7d4fd4510721dba420929f35bea2'
     ports:
       - "3000:3000"
     links:
       - prometheus
     dns:
       - 8.8.8.8
   prometheus:
-    image: 'prom/prometheus'
+    image: 'prom/prometheus@sha256:a75c5a35bc21d7afe69551eefa3cb1e1fb1775fe759408007a66b54ec3de1f29'
     volumes:
       - ./prometheus/:/etc/prometheus/
     command: 
@@ -18,7 +18,7 @@ services:
     links:
       - traffic
   traffic:
-    image: 'ghcr.io/grafana/github-traffic'
+    image: 'ghcr.io/grafana/github-traffic@sha256:94a9546415e019484a5d3197138148d3ffcb17842c8e852584f03a9848e6f407'
     ports: 
       - "8001:8001"
     env_file: