librenms: Fix password to short (#9236)

* librenms-install.sh aktualisieren

* librenms.json aktualisieren

* Update credentials and add generation

* Update credentials and add generation

* Refactor LibreNMS credentials output format

Updated the script to change how LibreNMS credentials are written to the creds file, adding a header for clarity.

* remove empty line

* remove space

---------

Co-authored-by: CanbiZ <47820557+MickLesk@users.noreply.github.com>

frontend/public/json/librenms.json

@@ -28,8 +28,13 @@
     }
   ],
   "default_credentials": {
-    "username": "admin",
-    "password": "admin"
+    "username": null,
+    "password": null
   },
-  "notes": []
+  "notes": [
+    {
+      "text": "After installation, the admin user credentials are saved in the file ~/librenms.creds inside the container.",
+      "type": "info"
+    }
+  ]
 }