ci: added controller version update through renovate

Author: Tbaile

renovate.json

@@ -2,5 +2,18 @@
   "$schema": "https://docs.renovatebot.com/renovate-schema.json",
   "extends": [
     "local>NethServer/.github:ns8"
+  ],
+  "customManagers": [
+    {
+      "customType": "regex",
+      "fileMatch": [
+        "build-images.sh"
+      ],
+      "matchStrings": [
+        "controller_version=\"(?<currentValue>[-0-9a-zA-Z_.]+)\""
+      ],
+      "depNameTemplate": "NethServer/nethsecurity-controller",
+      "datasourceTemplate": "github-releases"
+    }
   ]
-}
+}