Update portainer/portainer-ce Docker tag to v2.31.0

Reviewed-on: #4

docker-compose.yml

@@ -2,7 +2,7 @@ name: portainer
 
 services:
   portainer-ce:
-    image: portainer/portainer-ce:2.28.1
+    image: portainer/portainer-ce:2.31.0
     container_name: portainer
     restart: unless-stopped
     volumes:

renovate.json

@@ -8,7 +8,8 @@
   "packageRules": [
     {
       "matchUpdateTypes": ["minor", "patch"],
-      "automerge": true
+      "automerge": true,
+      "ignoreTests": true
     }
   ]
 }