Merge pull request 'Migrate renovate config' (#17) from renovate/migrate-config into main

Reviewed-on: kovagoadi.hu/static.kovagoadi.hu#17

renovate.json

@@ -3,9 +3,12 @@
   "extends": [
     "config:recommended"
   ],
-  "packageRules": [{
+  "packageRules": [
-    "docker": {
+    {
+      "matchCategories": [
+        "docker"
+      ],
       "pinDigests": true
     }
-  }]
+  ]
 }