grafana: set uid for "Archived Packages" dashboard

Grafana complains otherwise:

logger=provisioning.dashboard type=file name=default
t=2023-12-23T21:25:35.96456815Z level=error msg="failed to save dashboard"
file=/var/lib/grafana/dashboards/dashboards/archive.json
error="Unique identifier needed to be able to get a dashboard"

roles/grafana/files/dashboards/archive.json

@@ -228,6 +228,6 @@
   "timepicker": {},
   "timezone": "",
   "title": "Arch Linux Archive",
-  "uid": null,
+  "uid": "HHiAjmNVz",
   "version": 0
 }