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.yml

@@ -1,11 +1,11 @@
 services:
   ngrok:
-    image: ngrok/ngrok:latest
+    image: ngrok/ngrok:latest@sha256:141f5645c298975b82e641dc62742bef49a8772dcdb6a90f1195f9afb6bf2bfa
     command: http --url=${NGROK_SUBDOMAIN} grafana:3000
     environment:
       NGROK_AUTHTOKEN: ${NGROK_AUTHTOKEN}
   grafana:
-    image: grafana/grafana:main
+    image: grafana/grafana:main@sha256:8616bdf5c30708c10826b548fd0bfaa696b1765418e22c1264f30a0b07bb09cf
     environment:
       - GF_FEATURE_TOGGLES_ENABLE=provisioning,kubernetesDashboards
       - GF_RENDERING_SERVER_URL=http://renderer:8081/render
@@ -21,7 +21,7 @@ services:
       - ngrok
     restart: unless-stopped
   renderer:
-    image: grafana/grafana-image-renderer:latest
+    image: grafana/grafana-image-renderer:latest@sha256:273c059618110d1d6d32154cefd235e3a8d29fda2425d03d054f37e4b740349b
     ports:
       - 8081