group (#45)

renovate.json5

@@ -5,6 +5,8 @@
   ],
   "packageRules": [
     {
+      "groupName": "Docker images",
+      "groupSlug": "dockerimages",
       "matchDatasources": ["docker"],
       "pinDigests": true
     }
@@ -23,4 +25,4 @@
       "datasourceTemplate": "docker"
     }
   ]
-}
+}